21900432811 has 4 divisors (see below), whose sum is σ = 21914374824. Its totient is φ = 21886490800.

The previous prime is 21900432803. The next prime is 21900432823. The reversal of 21900432811 is 11823400912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21900432811 - 2³ = 21900432803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21900432881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6968650 + ... + 6971791.

It is an arithmetic number, because the mean of its divisors is an integer number (5478593706).

Almost surely, 2^21900432811 is an apocalyptic number.

21900432811 is a deficient number, since it is larger than the sum of its proper divisors (13942013).

21900432811 is a wasteful number, since it uses less digits than its factorization.

21900432811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13942012.

The product of its (nonzero) digits is 3456, while the sum is 31.

The spelling of 21900432811 in words is "twenty-one billion, nine hundred million, four hundred thirty-two thousand, eight hundred eleven".