161645511750 has 64 divisors (see below), whose sum is σ = 404740559808. Its totient is φ = 42969427200.

The previous prime is 161645511743. The next prime is 161645511799. The reversal of 161645511750 is 57115546161.

It is a super-2 number, since 2×161645511750² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 102199 + ... + 577698.

It is an arithmetic number, because the mean of its divisors is an integer number (6324071247).

Almost surely, 2^161645511750 is an apocalyptic number.

161645511750 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161645511750 is an abundant number, since it is smaller than the sum of its proper divisors (243095048058).

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

161645511750 is a wasteful number, since it uses less digits than its factorization.

161645511750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680234 (or 680224 counting only the distinct ones).

The product of its (nonzero) digits is 126000, while the sum is 42.

The spelling of 161645511750 in words is "one hundred sixty-one billion, six hundred forty-five million, five hundred eleven thousand, seven hundred fifty".