21300765 has 16 divisors (see below), whose sum is σ = 34214400. Its totient is φ = 11316032.

The previous prime is 21300757. The next prime is 21300791. The reversal of 21300765 is 56700312.

It is a cyclic number.

It is not a de Polignac number, because 21300765 - 2³ = 21300757 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1396 + ... + 6674.

It is an arithmetic number, because the mean of its divisors is an integer number (2138400).

Almost surely, 2^21300765 is an apocalyptic number.

It is an amenable number.

21300765 is a deficient number, since it is larger than the sum of its proper divisors (12913635).

21300765 is a wasteful number, since it uses less digits than its factorization.

21300765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5556.

The product of its (nonzero) digits is 1260, while the sum is 24.

The square root of 21300765 is about 4615.2751813949. The cubic root of 21300765 is about 277.2033027265.

The spelling of 21300765 in words is "twenty-one million, three hundred thousand, seven hundred sixty-five".