21930886 has 8 divisors (see below), whose sum is σ = 32916240. Its totient is φ = 10958808.

The previous prime is 21930877. The next prime is 21930893. The reversal of 21930886 is 68803912.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4455 + ... + 7981.

It is an arithmetic number, because the mean of its divisors is an integer number (4114530).

Almost surely, 2^21930886 is an apocalyptic number.

21930886 is a deficient number, since it is larger than the sum of its proper divisors (10985354).

21930886 is a wasteful number, since it uses less digits than its factorization.

21930886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6638.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 21930886 is about 4683.0423871667. The cubic root of 21930886 is about 279.9102007953.

The spelling of 21930886 in words is "twenty-one million, nine hundred thirty thousand, eight hundred eighty-six".