161662639536 has 240 divisors, whose sum is σ = 497426162688. Its totient is φ = 50738400000.

The previous prime is 161662639531. The next prime is 161662639547. The reversal of 161662639536 is 635936266161.

It is a happy number.

161662639536 is a `hidden beast` number, since 1 + 6 + 1 + 6 + 626 + 3 + 9 + 5 + 3 + 6 = 666.

It is a super-2 number, since 2×161662639536² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (161662639531) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4441411 + ... + 4477661.

Almost surely, 2^161662639536 is an apocalyptic number.

161662639536 is a gapful number since it is divisible by the number (16) 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 161662639536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (248713081344).

161662639536 is an abundant number, since it is smaller than the sum of its proper divisors (335763523152).

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

161662639536 is a wasteful number, since it uses less digits than its factorization.

161662639536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36342 (or 36324 counting only the distinct ones).

The product of its digits is 6298560, while the sum is 54.

The spelling of 161662639536 in words is "one hundred sixty-one billion, six hundred sixty-two million, six hundred thirty-nine thousand, five hundred thirty-six".