21386792 has 32 divisors (see below), whose sum is σ = 46612800. Its totient is φ = 9009024.

The previous prime is 21386791. The next prime is 21386797. The reversal of 21386792 is 29768312.

It is not an unprimeable number, because it can be changed into a prime (21386791) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68 + ... + 6540.

It is an arithmetic number, because the mean of its divisors is an integer number (1456650).

Almost surely, 2^21386792 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21386792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23306400).

21386792 is an abundant number, since it is smaller than the sum of its proper divisors (25226008).

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

21386792 is a wasteful number, since it uses less digits than its factorization.

21386792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6545 (or 6541 counting only the distinct ones).

The product of its digits is 36288, while the sum is 38.

The square root of 21386792 is about 4624.5856030568. The cubic root of 21386792 is about 277.5759800603.

The spelling of 21386792 in words is "twenty-one million, three hundred eighty-six thousand, seven hundred ninety-two".