21156179466 has 32 divisors (see below), whose sum is σ = 43326858240. Its totient is φ = 6883770096.

The previous prime is 21156179453. The next prime is 21156179477. The reversal of 21156179466 is 66497165112.

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, 7905 + ... + 205851.

It is an arithmetic number, because the mean of its divisors is an integer number (1353964320).

Almost surely, 2^21156179466 is an apocalyptic number.

21156179466 is an abundant number, since it is smaller than the sum of its proper divisors (22170678774).

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

21156179466 is a wasteful number, since it uses less digits than its factorization.

21156179466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198378.

The product of its digits is 544320, while the sum is 48.

The spelling of 21156179466 in words is "twenty-one billion, one hundred fifty-six million, one hundred seventy-nine thousand, four hundred sixty-six".