21516783703 has 16 divisors (see below), whose sum is σ = 23241142080. Its totient is φ = 19844338176.

The previous prime is 21516783679. The next prime is 21516783709. The reversal of 21516783703 is 30738761512.

It is a cyclic number.

It is not a de Polignac number, because 21516783703 - 2⁵ = 21516783671 is a prime.

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 21516783703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21516783709) 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, 732526 + ... + 761332.

It is an arithmetic number, because the mean of its divisors is an integer number (1452571380).

Almost surely, 2^21516783703 is an apocalyptic number.

21516783703 is a deficient number, since it is larger than the sum of its proper divisors (1724358377).

21516783703 is a wasteful number, since it uses less digits than its factorization.

21516783703 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29706.

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 21516783703 in words is "twenty-one billion, five hundred sixteen million, seven hundred eighty-three thousand, seven hundred three".