167978661904 has 45 divisors (see below), whose sum is σ = 329884880157. Its totient is φ = 82862237952.

The previous prime is 167978661899. The next prime is 167978661943. The reversal of 167978661904 is 409166879761.

The square root of 167978661904 is 409852.

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

It can be written as a sum of positive squares in only one way, i.e., 167461008400 + 517653504 = 409220^2 + 22752^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 129512584 + ... + 129513880.

Almost surely, 2^167978661904 is an apocalyptic number.

167978661904 is the 409852-nd square number.

It is an amenable number.

167978661904 is a deficient number, since it is larger than the sum of its proper divisors (161906218253).

167978661904 is an frugal number, since it uses more digits than its factorization.

167978661904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2760 (or 1378 counting only the distinct ones).

The product of its (nonzero) digits is 27433728, while the sum is 64.

Multiplying 167978661904 by its sum of digits (64), we get a square (10750634361856 = 3278816²).

The spelling of 167978661904 in words is "one hundred sixty-seven billion, nine hundred seventy-eight million, six hundred sixty-one thousand, nine hundred four".