21702464 has 56 divisors (see below), whose sum is σ = 49670208. Its totient is φ = 9216000.

The previous prime is 21702431. The next prime is 21702479. The reversal of 21702464 is 46420712.

It is a tau number, because it is divible by the number of its divisors (56).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86339 + ... + 86589.

It is an arithmetic number, because the mean of its divisors is an integer number (886968).

Almost surely, 2^21702464 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 21702464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24835104).

21702464 is an abundant number, since it is smaller than the sum of its proper divisors (27967744).

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

21702464 is a wasteful number, since it uses less digits than its factorization.

21702464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 21702464 is about 4658.5903447288. The cubic root of 21702464 is about 278.9350019662.

The spelling of 21702464 in words is "twenty-one million, seven hundred two thousand, four hundred sixty-four".