21053799 has 12 divisors (see below), whose sum is σ = 32750536. Its totient is φ = 12956112.

The previous prime is 21053783. The next prime is 21053831. The reversal of 21053799 is 99735012.

It is not a de Polignac number, because 21053799 - 2⁴ = 21053783 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21053099) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 89857 + ... + 90090.

Almost surely, 2^21053799 is an apocalyptic number.

21053799 is a deficient number, since it is larger than the sum of its proper divisors (11696737).

21053799 is a wasteful number, since it uses less digits than its factorization.

21053799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179966 (or 179963 counting only the distinct ones).

The product of its (nonzero) digits is 17010, while the sum is 36.

The square root of 21053799 is about 4588.4418924075. The cubic root of 21053799 is about 276.1278157206.

The spelling of 21053799 in words is "twenty-one million, fifty-three thousand, seven hundred ninety-nine".