21531796 has 24 divisors (see below), whose sum is σ = 44269344. Its totient is φ = 9034080.

The previous prime is 21531793. The next prime is 21531799. The reversal of 21531796 is 69713512.

It is an interprime number because it is at equal distance from previous prime (21531793) and next prime (21531799).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21531793) 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, 18250 + ... + 19393.

It is an arithmetic number, because the mean of its divisors is an integer number (1844556).

Almost surely, 2^21531796 is an apocalyptic number.

21531796 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21531796 is an abundant number, since it is smaller than the sum of its proper divisors (22737548).

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

21531796 is a wasteful number, since it uses less digits than its factorization.

21531796 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37671 (or 37669 counting only the distinct ones).

The product of its digits is 11340, while the sum is 34.

The square root of 21531796 is about 4640.2366318971. The cubic root of 21531796 is about 278.2018960210.

The spelling of 21531796 in words is "twenty-one million, five hundred thirty-one thousand, seven hundred ninety-six".