21337225 has 48 divisors (see below), whose sum is σ = 33247872. Its totient is φ = 13224960.

The previous prime is 21337219. The next prime is 21337231. The reversal of 21337225 is 52273312.

21337225 = T₆ + T₇ + ... + T₅₀₃.

It is an interprime number because it is at equal distance from previous prime (21337219) and next prime (21337231).

It is not a de Polignac number, because 21337225 - 2⁹ = 21336713 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 21337225.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 188769 + ... + 188881.

It is an arithmetic number, because the mean of its divisors is an integer number (692664).

Almost surely, 2^21337225 is an apocalyptic number.

21337225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21337225 is a deficient number, since it is larger than the sum of its proper divisors (11910647).

21337225 is a wasteful number, since it uses less digits than its factorization.

21337225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 221 counting only the distinct ones).

The product of its digits is 2520, while the sum is 25.

The square root of 21337225 is about 4619.2234195804. The cubic root of 21337225 is about 277.3613732834.

The spelling of 21337225 in words is "twenty-one million, three hundred thirty-seven thousand, two hundred twenty-five".