21508088 has 32 divisors (see below), whose sum is σ = 46310400. Its totient is φ = 9173472.

The previous prime is 21508087. The next prime is 21508099. The reversal of 21508088 is 88080512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21508087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12581 + ... + 14187.

It is an arithmetic number, because the mean of its divisors is an integer number (1447200).

Almost surely, 2^21508088 is an apocalyptic number.

21508088 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21508088 is an abundant number, since it is smaller than the sum of its proper divisors (24802312).

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

21508088 is a wasteful number, since it uses less digits than its factorization.

21508088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1859 (or 1855 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 32.

The square root of 21508088 is about 4637.6813172101. The cubic root of 21508088 is about 278.0997519984.

The spelling of 21508088 in words is "twenty-one million, five hundred eight thousand, eighty-eight".