21880766 has 8 divisors (see below), whose sum is σ = 32863320. Its totient is φ = 10926328.

The previous prime is 21880763. The next prime is 21880787. The reversal of 21880766 is 66708812.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21880763) 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, 4961 + ... + 8268.

It is an arithmetic number, because the mean of its divisors is an integer number (4107915).

Almost surely, 2^21880766 is an apocalyptic number.

21880766 is a deficient number, since it is larger than the sum of its proper divisors (10982554).

21880766 is a wasteful number, since it uses less digits than its factorization.

21880766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14058.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 21880766 is about 4677.6881041814. The cubic root of 21880766 is about 279.6968061633.

The spelling of 21880766 in words is "twenty-one million, eight hundred eighty thousand, seven hundred sixty-six".