20172040 has 32 divisors (see below), whose sum is σ = 51871680. Its totient is φ = 6916032.

The previous prime is 20172037. The next prime is 20172073. The reversal of 20172040 is 4027102.

It is a super-2 number, since 2×20172040² = 813822395523200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35742 + ... + 36301.

It is an arithmetic number, because the mean of its divisors is an integer number (1620990).

Almost surely, 2^20172040 is an apocalyptic number.

20172040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20172040 is an abundant number, since it is smaller than the sum of its proper divisors (31699640).

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

20172040 is a wasteful number, since it uses less digits than its factorization.

20172040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72061 (or 72057 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 20172040 is about 4491.3294245691. The cubic root of 20172040 is about 272.2178545892.

Adding to 20172040 its reverse (4027102), we get a palindrome (24199142).

The spelling of 20172040 in words is "twenty million, one hundred seventy-two thousand, forty".