21987023519 has 8 divisors (see below), whose sum is σ = 22290824640. Its totient is φ = 21683293056.

The previous prime is 21987023501. The next prime is 21987023521. The reversal of 21987023519 is 91532078912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21987023519 - 2⁸ = 21987023263 is a prime.

It is a super-2 number, since 2×21987023519² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21987023579) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1050842 + ... + 1071560.

It is an arithmetic number, because the mean of its divisors is an integer number (2786353080).

Almost surely, 2^21987023519 is an apocalyptic number.

21987023519 is a deficient number, since it is larger than the sum of its proper divisors (303801121).

21987023519 is a wasteful number, since it uses less digits than its factorization.

21987023519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35329.

The product of its (nonzero) digits is 272160, while the sum is 47.

The spelling of 21987023519 in words is "twenty-one billion, nine hundred eighty-seven million, twenty-three thousand, five hundred nineteen".