21007896 has 64 divisors (see below), whose sum is σ = 64646400. Its totient is φ = 5539968.

The previous prime is 21007891. The next prime is 21007913. The reversal of 21007896 is 69870012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21007891) 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, 2626 + ... + 6993.

It is an arithmetic number, because the mean of its divisors is an integer number (1010100).

Almost surely, 2^21007896 is an apocalyptic number.

21007896 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21007896 is an abundant number, since it is smaller than the sum of its proper divisors (43638504).

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

21007896 is a wasteful number, since it uses less digits than its factorization.

21007896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9648 (or 9644 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 21007896 is about 4583.4371382184. The cubic root of 21007896 is about 275.9269918215.

The spelling of 21007896 in words is "twenty-one million, seven thousand, eight hundred ninety-six".