21104577 has 16 divisors (see below), whose sum is σ = 33671680. Its totient is φ = 12987216.

The previous prime is 21104569. The next prime is 21104591. The reversal of 21104577 is 77540112.

It is not a de Polignac number, because 21104577 - 2³ = 21104569 is a prime.

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

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21104577.

It is not an unprimeable number, because it can be changed into a prime (21104507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29713 + ... + 30414.

It is an arithmetic number, because the mean of its divisors is an integer number (2104480).

Almost surely, 2^21104577 is an apocalyptic number.

21104577 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21104577 is a deficient number, since it is larger than the sum of its proper divisors (12567103).

21104577 is a wasteful number, since it uses less digits than its factorization.

21104577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60149 (or 60143 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 27.

The square root of 21104577 is about 4593.9718109714. The cubic root of 21104577 is about 276.3496278043.

Adding to 21104577 its reverse (77540112), we get a palindrome (98644689).

The spelling of 21104577 in words is "twenty-one million, one hundred four thousand, five hundred seventy-seven".