21275771770 has 32 divisors (see below), whose sum is σ = 42749467200. Its totient is φ = 7556720640.

The previous prime is 21275771761. The next prime is 21275771807. The reversal of 21275771770 is 7717757212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21275771770.

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, 2244295 + ... + 2253754.

It is an arithmetic number, because the mean of its divisors is an integer number (1335920850).

Almost surely, 2^21275771770 is an apocalyptic number.

21275771770 is an abundant number, since it is smaller than the sum of its proper divisors (21473695430).

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

21275771770 is a wasteful number, since it uses less digits than its factorization.

21275771770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4498110.

The product of its (nonzero) digits is 336140, while the sum is 46.

The spelling of 21275771770 in words is "twenty-one billion, two hundred seventy-five million, seven hundred seventy-one thousand, seven hundred seventy".