21383377515 has 40 divisors (see below), whose sum is σ = 38342243808. Its totient is φ = 11401326720.

The previous prime is 21383377481. The next prime is 21383377523. The reversal of 21383377515 is 51577338312.

21383377515 is a `hidden beast` number, since 2 + 1 + 38 + 33 + 77 + 515 = 666.

It is not a de Polignac number, because 21383377515 - 2⁶ = 21383377451 is a prime.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2824335 + ... + 2831895.

Almost surely, 2^21383377515 is an apocalyptic number.

21383377515 is a deficient number, since it is larger than the sum of its proper divisors (16958866293).

21383377515 is an equidigital number, since it uses as much as digits as its factorization.

21383377515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14561 (or 14552 counting only the distinct ones).

The product of its digits is 529200, while the sum is 45.

The spelling of 21383377515 in words is "twenty-one billion, three hundred eighty-three million, three hundred seventy-seven thousand, five hundred fifteen".