21277164072 has 32 divisors (see below), whose sum is σ = 53255030400. Its totient is φ = 7084105344.

The previous prime is 21277164059. The next prime is 21277164121. The reversal of 21277164072 is 27046177212.

It is a self number, because there is not a number n which added to its sum of digits gives 21277164072.

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, 496672 + ... + 537807.

It is an arithmetic number, because the mean of its divisors is an integer number (1664219700).

Almost surely, 2^21277164072 is an apocalyptic number.

It is an amenable number.

21277164072 is an abundant number, since it is smaller than the sum of its proper divisors (31977866328).

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

21277164072 is a wasteful number, since it uses less digits than its factorization.

21277164072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1035345 (or 1035341 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 39.

The spelling of 21277164072 in words is "twenty-one billion, two hundred seventy-seven million, one hundred sixty-four thousand, seventy-two".