21025072 has 20 divisors (see below), whose sum is σ = 41120136. Its totient is φ = 10413440.

The previous prime is 21025051. The next prime is 21025091. The reversal of 21025072 is 27052012.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4429 + ... + 7852.

Almost surely, 2^21025072 is an apocalyptic number.

It is an amenable number.

21025072 is a deficient number, since it is larger than the sum of its proper divisors (20095064).

21025072 is a wasteful number, since it uses less digits than its factorization.

21025072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12396 (or 12390 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 21025072 is about 4585.3104584096. The cubic root of 21025072 is about 276.0021703953.

Adding to 21025072 its reverse (27052012), we get a palindrome (48077084).

The spelling of 21025072 in words is "twenty-one million, twenty-five thousand, seventy-two".