181928693961 has 81 divisors (see below), whose sum is σ = 322927511751. Its totient is φ = 98395583328.

The previous prime is 181928693953. The next prime is 181928693987. The reversal of 181928693961 is 169396829181.

The square root of 181928693961 is 426531.

It is a perfect power (a square), and thus also a powerful number.

181928693961 is a `hidden beast` number, since 1 + 81 + 92 + 86 + 9 + 396 + 1 = 666.

181928693961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 85070805561 + 96857888400 = 291669^2 + 311220^2 .

It is not a de Polignac number, because 181928693961 - 2³ = 181928693953 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (181928691961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 170185335 + ... + 170186403.

Almost surely, 2^181928693961 is an apocalyptic number.

181928693961 is the 426531-st square number.

181928693961 is the 213266-th centered octagonal number.

It is an amenable number.

181928693961 is a deficient number, since it is larger than the sum of its proper divisors (140998817790).

181928693961 is an equidigital number, since it uses as much as digits as its factorization.

181928693961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2196 (or 1098 counting only the distinct ones).

The product of its digits is 10077696, while the sum is 63.

The spelling of 181928693961 in words is "one hundred eighty-one billion, nine hundred twenty-eight million, six hundred ninety-three thousand, nine hundred sixty-one".