21325788 has 96 divisors (see below), whose sum is σ = 62496000. Its totient is φ = 6229440.

The previous prime is 21325757. The next prime is 21325819. The reversal of 21325788 is 88752312.

It is an interprime number because it is at equal distance from previous prime (21325757) and next prime (21325819).

It is a Harshad number since it is a multiple of its sum of digits (36).

Its product of digits (26880) is a multiple of the sum of its prime factors (672).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34143 + ... + 34761.

It is an arithmetic number, because the mean of its divisors is an integer number (651000).

Almost surely, 2^21325788 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 21325788, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31248000).

21325788 is an abundant number, since it is smaller than the sum of its proper divisors (41170212).

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

21325788 is a wasteful number, since it uses less digits than its factorization.

21325788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 672 (or 664 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 21325788 is about 4617.9852749874. The cubic root of 21325788 is about 277.3118081225.

The spelling of 21325788 in words is "twenty-one million, three hundred twenty-five thousand, seven hundred eighty-eight".