21320754 has 64 divisors (see below), whose sum is σ = 55593216. Its totient is φ = 5289984.

The previous prime is 21320749. The next prime is 21320801. The reversal of 21320754 is 45702312.

It is a super-2 number, since 2×21320754² = 909149102257032, which contains 22 as substring.

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, 8134 + ... + 10430.

It is an arithmetic number, because the mean of its divisors is an integer number (868644).

Almost surely, 2^21320754 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21320754, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27796608).

21320754 is an abundant number, since it is smaller than the sum of its proper divisors (34272462).

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

21320754 is a wasteful number, since it uses less digits than its factorization.

21320754 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2339.

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 21320754 is about 4617.4401999376. The cubic root of 21320754 is about 277.2899863810.

The spelling of 21320754 in words is "twenty-one million, three hundred twenty thousand, seven hundred fifty-four".