21831902 has 4 divisors (see below), whose sum is σ = 32747856. Its totient is φ = 10915950.

The previous prime is 21831881. The next prime is 21831911. The reversal of 21831902 is 20913812.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5457974 + ... + 5457977.

It is an arithmetic number, because the mean of its divisors is an integer number (8186964).

Almost surely, 2^21831902 is an apocalyptic number.

21831902 is a deficient number, since it is larger than the sum of its proper divisors (10915954).

21831902 is a wasteful number, since it uses less digits than its factorization.

21831902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10915953.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 21831902 is about 4672.4620918740. The cubic root of 21831902 is about 279.4884452198.

The spelling of 21831902 in words is "twenty-one million, eight hundred thirty-one thousand, nine hundred two".