21966725 has 36 divisors (see below), whose sum is σ = 31268832. Its totient is φ = 15180000.

The previous prime is 21966691. The next prime is 21966727. The reversal of 21966725 is 52766912.

It is a happy number.

It is not a de Polignac number, because 21966725 - 2²² = 17772421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21966727) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 145400 + ... + 145550.

Almost surely, 2^21966725 is an apocalyptic number.

21966725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21966725 is a deficient number, since it is larger than the sum of its proper divisors (9302107).

21966725 is a wasteful number, since it uses less digits than its factorization.

21966725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218 (or 190 counting only the distinct ones).

The product of its digits is 45360, while the sum is 38.

The square root of 21966725 is about 4686.8672906324. The cubic root of 21966725 is about 280.0625922993.

The spelling of 21966725 in words is "twenty-one million, nine hundred sixty-six thousand, seven hundred twenty-five".