161555115390 has 64 divisors (see below), whose sum is σ = 419170083840. Its totient is φ = 39710839680.

The previous prime is 161555115383. The next prime is 161555115443. The reversal of 161555115390 is 93511555161.

It is a happy number.

It is a super-2 number, since 2×161555115390² (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, 3809046 + ... + 3851225.

It is an arithmetic number, because the mean of its divisors is an integer number (6549532560).

Almost surely, 2^161555115390 is an apocalyptic number.

161555115390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161555115390 is an abundant number, since it is smaller than the sum of its proper divisors (257614968450).

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

161555115390 is a wasteful number, since it uses less digits than its factorization.

161555115390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7660337.

The product of its (nonzero) digits is 101250, while the sum is 42.

The spelling of 161555115390 in words is "one hundred sixty-one billion, five hundred fifty-five million, one hundred fifteen thousand, three hundred ninety".