21377810811 has 32 divisors (see below), whose sum is σ = 34629493248. Its totient is φ = 11451456000.

The previous prime is 21377810789. The next prime is 21377810821. The reversal of 21377810811 is 11801877312.

It is not a de Polignac number, because 21377810811 - 2⁶ = 21377810747 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21377810811.

It is not an unprimeable number, because it can be changed into a prime (21377810821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29680 + ... + 208893.

It is an arithmetic number, because the mean of its divisors is an integer number (1082171664).

Almost surely, 2^21377810811 is an apocalyptic number.

21377810811 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21377810811 is a deficient number, since it is larger than the sum of its proper divisors (13251682437).

21377810811 is a wasteful number, since it uses less digits than its factorization.

21377810811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238851.

The product of its (nonzero) digits is 18816, while the sum is 39.

The spelling of 21377810811 in words is "twenty-one billion, three hundred seventy-seven million, eight hundred ten thousand, eight hundred eleven".