21015652239 has 24 divisors (see below), whose sum is σ = 31140974592. Its totient is φ = 13650788880.

The previous prime is 21015652201. The next prime is 21015652291. The reversal of 21015652239 is 93225651012.

It is a happy number.

It is not a de Polignac number, because 21015652239 - 2¹¹ = 21015650191 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21015652939) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17067 + ... + 205724.

It is an arithmetic number, because the mean of its divisors is an integer number (1297540608).

Almost surely, 2^21015652239 is an apocalyptic number.

21015652239 is a deficient number, since it is larger than the sum of its proper divisors (10125322353).

21015652239 is a wasteful number, since it uses less digits than its factorization.

21015652239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223067 (or 223064 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The spelling of 21015652239 in words is "twenty-one billion, fifteen million, six hundred fifty-two thousand, two hundred thirty-nine".