21880811 has 8 divisors (see below), whose sum is σ = 22116864. Its totient is φ = 21646440.

The previous prime is 21880787. The next prime is 21880829. The reversal of 21880811 is 11808812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21880811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21882811) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71120 + ... + 71426.

It is an arithmetic number, because the mean of its divisors is an integer number (2764608).

Almost surely, 2^21880811 is an apocalyptic number.

21880811 is a deficient number, since it is larger than the sum of its proper divisors (236053).

21880811 is a wasteful number, since it uses less digits than its factorization.

21880811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841.

The product of its (nonzero) digits is 1024, while the sum is 29.

The square root of 21880811 is about 4677.6929142474. The cubic root of 21880811 is about 279.6969979047.

The spelling of 21880811 in words is "twenty-one million, eight hundred eighty thousand, eight hundred eleven".