21283863615 has 64 divisors (see below), whose sum is σ = 43729459200. Its totient is φ = 9620404992.

The previous prime is 21283863613. The next prime is 21283863637. The reversal of 21283863615 is 51636838212.

21283863615 is a `hidden beast` number, since 2 + 1 + 2 + 8 + 3 + 8 + 636 + 1 + 5 = 666.

It is not a de Polignac number, because 21283863615 - 2¹ = 21283863613 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21283863613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 42427 + ... + 210636.

It is an arithmetic number, because the mean of its divisors is an integer number (683272800).

Almost surely, 2^21283863615 is an apocalyptic number.

21283863615 is an abundant number, since it is smaller than the sum of its proper divisors (22445595585).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21283863615 is a wasteful number, since it uses less digits than its factorization.

21283863615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253173 (or 253167 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The spelling of 21283863615 in words is "twenty-one billion, two hundred eighty-three million, eight hundred sixty-three thousand, six hundred fifteen".