21660550746 has 16 divisors (see below), whose sum is σ = 43346294208. Its totient is φ = 7215984800.

The previous prime is 21660550699. The next prime is 21660550757. The reversal of 21660550746 is 64705506612.

It is a junction number, because it is equal to n+sod(n) for n = 21660550698 and 21660550707.

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, 1038510 + ... + 1059161.

It is an arithmetic number, because the mean of its divisors is an integer number (2709143388).

Almost surely, 2^21660550746 is an apocalyptic number.

21660550746 is an abundant number, since it is smaller than the sum of its proper divisors (21685743462).

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

21660550746 is a wasteful number, since it uses less digits than its factorization.

21660550746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2099397.

The product of its (nonzero) digits is 302400, while the sum is 42.

The spelling of 21660550746 in words is "twenty-one billion, six hundred sixty million, five hundred fifty thousand, seven hundred forty-six".