40172420 has 12 divisors (see below), whose sum is σ = 84362124. Its totient is φ = 16068960.

The previous prime is 40172413. The next prime is 40172423. The reversal of 40172420 is 2427104.

40172420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 27541504 + 12630916 = 5248^2 + 3554^2 .

It is a super-2 number, since 2×40172420² = 3227646657312800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 2008621 = 40172420 / (4 + 0 + 1 + 7 + 2 + 4 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 40172392 and 40172401.

It is not an unprimeable number, because it can be changed into a prime (40172423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1004291 + ... + 1004330.

It is an arithmetic number, because the mean of its divisors is an integer number (7030177).

Almost surely, 2^40172420 is an apocalyptic number.

It is an amenable number.

40172420 is an abundant number, since it is smaller than the sum of its proper divisors (44189704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

40172420 is a wasteful number, since it uses less digits than its factorization.

40172420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2008630 (or 2008628 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 20.

The square root of 40172420 is about 6338.1716606605. The cubic root of 40172420 is about 342.4858750635.

Adding to 40172420 its reverse (2427104), we get a palindrome (42599524).

The spelling of 40172420 in words is "forty million, one hundred seventy-two thousand, four hundred twenty".