161872540 has 12 divisors (see below), whose sum is σ = 339932376. Its totient is φ = 64749008.

The previous prime is 161872531. The next prime is 161872541. The reversal of 161872540 is 45278161.

It is a junction number, because it is equal to n+sod(n) for n = 161872496 and 161872505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161872541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4046794 + ... + 4046833.

It is an arithmetic number, because the mean of its divisors is an integer number (28327698).

Almost surely, 2^161872540 is an apocalyptic number.

161872540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161872540 is an abundant number, since it is smaller than the sum of its proper divisors (178059836).

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

161872540 is a wasteful number, since it uses less digits than its factorization.

161872540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8093636 (or 8093634 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 161872540 is about 12722.9139744007. The cubic root of 161872540 is about 544.9931710841.

The spelling of 161872540 in words is "one hundred sixty-one million, eight hundred seventy-two thousand, five hundred forty".