21011583799 has 4 divisors (see below), whose sum is σ = 21011974960. Its totient is φ = 21011192640.

The previous prime is 21011583793. The next prime is 21011583821. The reversal of 21011583799 is 99738511012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21011583799 - 2⁵ = 21011583767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011583793) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99162 + ... + 227719.

It is an arithmetic number, because the mean of its divisors is an integer number (5252993740).

Almost surely, 2^21011583799 is an apocalyptic number.

21011583799 is a deficient number, since it is larger than the sum of its proper divisors (391161).

21011583799 is an equidigital number, since it uses as much as digits as its factorization.

21011583799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391160.

The product of its (nonzero) digits is 136080, while the sum is 46.

The spelling of 21011583799 in words is "twenty-one billion, eleven million, five hundred eighty-three thousand, seven hundred ninety-nine".