21919902 has 32 divisors (see below), whose sum is σ = 46635264. Its totient is φ = 6844800.

The previous prime is 21919847. The next prime is 21919903. The reversal of 21919902 is 20991912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21919903) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31377 + ... + 32067.

It is an arithmetic number, because the mean of its divisors is an integer number (1457352).

Almost surely, 2^21919902 is an apocalyptic number.

21919902 is an abundant number, since it is smaller than the sum of its proper divisors (24715362).

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

21919902 is a wasteful number, since it uses less digits than its factorization.

21919902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1024.

The product of its (nonzero) digits is 2916, while the sum is 33.

The square root of 21919902 is about 4681.8694983948. The cubic root of 21919902 is about 279.8634623419.

The spelling of 21919902 in words is "twenty-one million, nine hundred nineteen thousand, nine hundred two".