40208420 has 72 divisors (see below), whose sum is σ = 99542520. Its totient is φ = 13601280.

The previous prime is 40208411. The next prime is 40208429. The reversal of 40208420 is 2480204.

It is an interprime number because it is at equal distance from previous prime (40208411) and next prime (40208429).

It can be written as a sum of positive squares in 4 ways, for example, as 164836 + 40043584 = 406^2 + 6328^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 40208392 and 40208401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40208429) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86990 + ... + 87450.

It is an arithmetic number, because the mean of its divisors is an integer number (1382535).

Almost surely, 2^40208420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40208420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49771260).

40208420 is an abundant number, since it is smaller than the sum of its proper divisors (59334100).

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

40208420 is a wasteful number, since it uses less digits than its factorization.

40208420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573 (or 564 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 40208420 is about 6341.0109604069. The cubic root of 40208420 is about 342.5881492968.

Adding to 40208420 its reverse (2480204), we get a palindrome (42688624).

The spelling of 40208420 in words is "forty million, two hundred eight thousand, four hundred twenty".