21905934 has 8 divisors (see below), whose sum is σ = 43811880. Its totient is φ = 7301976.

The previous prime is 21905929. The next prime is 21905953. The reversal of 21905934 is 43950912.

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

21905934 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 21905895 and 21905904.

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, 1825489 + ... + 1825500.

It is an arithmetic number, because the mean of its divisors is an integer number (5476485).

Almost surely, 2^21905934 is an apocalyptic number.

21905934 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21905934 is a wasteful number, since it uses less digits than its factorization.

21905934 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3650994.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 21905934 is about 4680.3775488736. The cubic root of 21905934 is about 279.8040039941.

The spelling of 21905934 in words is "twenty-one million, nine hundred five thousand, nine hundred thirty-four".