21170451634 has 16 divisors (see below), whose sum is σ = 31980140640. Its totient is φ = 10510637760.

The previous prime is 21170451629. The next prime is 21170451647. The reversal of 21170451634 is 43615407112.

It is a self number, because there is not a number n which added to its sum of digits gives 21170451634.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124797 + ... + 240655.

It is an arithmetic number, because the mean of its divisors is an integer number (1998758790).

Almost surely, 2^21170451634 is an apocalyptic number.

21170451634 is a deficient number, since it is larger than the sum of its proper divisors (10809689006).

21170451634 is a wasteful number, since it uses less digits than its factorization.

21170451634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116505.

The product of its (nonzero) digits is 20160, while the sum is 34.

Adding to 21170451634 its reverse (43615407112), we get a palindrome (64785858746).

The spelling of 21170451634 in words is "twenty-one billion, one hundred seventy million, four hundred fifty-one thousand, six hundred thirty-four".