21325761 has 20 divisors (see below), whose sum is σ = 33244992. Its totient is φ = 13597848.

The previous prime is 21325757. The next prime is 21325819. The reversal of 21325761 is 16752312.

It is a happy number.

It is not a de Polignac number, because 21325761 - 2² = 21325757 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21323761) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3861 + ... + 7586.

Almost surely, 2^21325761 is an apocalyptic number.

It is an amenable number.

21325761 is a deficient number, since it is larger than the sum of its proper divisors (11919231).

21325761 is a wasteful number, since it uses less digits than its factorization.

21325761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11482 (or 11473 counting only the distinct ones).

The product of its digits is 2520, while the sum is 27.

The square root of 21325761 is about 4617.9823516337. The cubic root of 21325761 is about 277.3116910901.

The spelling of 21325761 in words is "twenty-one million, three hundred twenty-five thousand, seven hundred sixty-one".