21702425 has 12 divisors (see below), whose sum is σ = 27237840. Its totient is φ = 17151120.

The previous prime is 21702419. The next prime is 21702431. The reversal of 21702425 is 52420712.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21702419) and next prime (21702431).

It is not a de Polignac number, because 21702425 - 2⁶ = 21702361 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21702425.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3155 + ... + 7304.

It is an arithmetic number, because the mean of its divisors is an integer number (2269820).

Almost surely, 2^21702425 is an apocalyptic number.

21702425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21702425 is a deficient number, since it is larger than the sum of its proper divisors (5535415).

21702425 is a wasteful number, since it uses less digits than its factorization.

21702425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10552 (or 10547 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 21702425 is about 4658.5861589113. The cubic root of 21702425 is about 278.9348348812.

The spelling of 21702425 in words is "twenty-one million, seven hundred two thousand, four hundred twenty-five".