156997440 has 196 divisors, whose sum is σ = 561351684. Its totient is φ = 41803776.

The previous prime is 156997417. The next prime is 156997453. The reversal of 156997440 is 44799651.

It can be written as a sum of positive squares in 2 ways, for example, as 53934336 + 103063104 = 7344^2 + 10152^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 27 ways as a sum of consecutive naturals, for example, 232944 + ... + 233616.

Almost surely, 2^156997440 is an apocalyptic number.

156997440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 156997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280675842).

156997440 is an abundant number, since it is smaller than the sum of its proper divisors (404354244).

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

156997440 is an frugal number, since it uses more digits than its factorization.

156997440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708 (or 683 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 156997440 is about 12529.8619306040. The cubic root of 156997440 is about 539.4661390489.

The spelling of 156997440 in words is "one hundred fifty-six million, nine hundred ninety-seven thousand, four hundred forty".