161561156661510 has 32 divisors (see below), whose sum is σ = 395996707395072. Its totient is φ = 42166316064480.

The previous prime is 161561156661479. The next prime is 161561156661547. The reversal of 161561156661510 is 15166651165161.

It is a super-2 number, since 2×161561156661510² (a number of 29 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 15 ways as a sum of consecutive naturals, for example, 57291188896 + ... + 57291191715.

It is an arithmetic number, because the mean of its divisors is an integer number (12374897106096).

Almost surely, 2^{161561156661510} is an apocalyptic number.

161561156661510 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161561156661510 is an abundant number, since it is smaller than the sum of its proper divisors (234435550733562).

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

161561156661510 is a wasteful number, since it uses less digits than its factorization.

161561156661510 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114582380668.

The product of its (nonzero) digits is 972000, while the sum is 51.

The spelling of 161561156661510 in words is "one hundred sixty-one trillion, five hundred sixty-one billion, one hundred fifty-six million, six hundred sixty-one thousand, five hundred ten".