21117357307 has 4 divisors (see below), whose sum is σ = 21311094640. Its totient is φ = 20923619976.

The previous prime is 21117357281. The next prime is 21117357323. The reversal of 21117357307 is 70375371112.

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 21117357307 - 2⁷ = 21117357179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21117357367) 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, 96868503 + ... + 96868720.

It is an arithmetic number, because the mean of its divisors is an integer number (5327773660).

Almost surely, 2^21117357307 is an apocalyptic number.

21117357307 is a deficient number, since it is larger than the sum of its proper divisors (193737333).

21117357307 is a wasteful number, since it uses less digits than its factorization.

21117357307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193737332.

The product of its (nonzero) digits is 30870, while the sum is 37.

The spelling of 21117357307 in words is "twenty-one billion, one hundred seventeen million, three hundred fifty-seven thousand, three hundred seven".