161772436 has 24 divisors (see below), whose sum is σ = 332291456. Its totient is φ = 67456800.

The previous prime is 161772431. The next prime is 161772437. The reversal of 161772436 is 634277161.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a junction number, because it is equal to n+sod(n) for n = 161772395 and 161772404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161772431) 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 7 ways as a sum of consecutive naturals, for example, 77040 + ... + 79111.

Almost surely, 2^161772436 is an apocalyptic number.

It is an amenable number.

161772436 is an abundant number, since it is smaller than the sum of its proper divisors (170519020).

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

161772436 is a wasteful number, since it uses less digits than its factorization.

161772436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156199 (or 156197 counting only the distinct ones).

The product of its digits is 42336, while the sum is 37.

The square root of 161772436 is about 12718.9793615683. The cubic root of 161772436 is about 544.8808043905.

The spelling of 161772436 in words is "one hundred sixty-one million, seven hundred seventy-two thousand, four hundred thirty-six".