21077365 has 32 divisors (see below), whose sum is σ = 29168640. Its totient is φ = 14515200.

The previous prime is 21077359. The next prime is 21077369. The reversal of 21077365 is 56377012.

It is not a de Polignac number, because 21077365 - 2⁵ = 21077333 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21077369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 49855 + ... + 50275.

It is an arithmetic number, because the mean of its divisors is an integer number (911520).

Almost surely, 2^21077365 is an apocalyptic number.

It is an amenable number.

21077365 is a deficient number, since it is larger than the sum of its proper divisors (8091275).

21077365 is a wasteful number, since it uses less digits than its factorization.

21077365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 493.

The product of its (nonzero) digits is 8820, while the sum is 31.

The square root of 21077365 is about 4591.0091483246. The cubic root of 21077365 is about 276.2308027036.

The spelling of 21077365 in words is "twenty-one million, seventy-seven thousand, three hundred sixty-five".