21257622 has 12 divisors (see below), whose sum is σ = 46058220. Its totient is φ = 7085868.

The previous prime is 21257581. The next prime is 21257651. The reversal of 21257622 is 22675212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 590472 + ... + 590507.

It is an arithmetic number, because the mean of its divisors is an integer number (3838185).

Almost surely, 2^21257622 is an apocalyptic number.

21257622 is an abundant number, since it is smaller than the sum of its proper divisors (24800598).

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

21257622 is a wasteful number, since it uses less digits than its factorization.

21257622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1180987 (or 1180984 counting only the distinct ones).

The product of its digits is 3360, while the sum is 27.

The square root of 21257622 is about 4610.5988765018. The cubic root of 21257622 is about 277.0160251734.

It can be divided in two parts, 2125762 and 2, that multiplied together give a palindrome (4251524).

The spelling of 21257622 in words is "twenty-one million, two hundred fifty-seven thousand, six hundred twenty-two".