21323777015 has 16 divisors (see below), whose sum is σ = 26109311040. Its totient is φ = 16714014720.

The previous prime is 21323776987. The next prime is 21323777039. The reversal of 21323777015 is 51077732312.

It is not a de Polignac number, because 21323777015 - 2¹⁸ = 21323514871 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21323777015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57635 + ... + 214404.

It is an arithmetic number, because the mean of its divisors is an integer number (1631831940).

Almost surely, 2^21323777015 is an apocalyptic number.

21323777015 is a deficient number, since it is larger than the sum of its proper divisors (4785534025).

21323777015 is a wasteful number, since it uses less digits than its factorization.

21323777015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272362.

The product of its (nonzero) digits is 61740, while the sum is 38.

The spelling of 21323777015 in words is "twenty-one billion, three hundred twenty-three million, seven hundred seventy-seven thousand, fifteen".