15652340021 has 4 divisors (see below), whose sum is σ = 15828209100. Its totient is φ = 15476470944.

The previous prime is 15652339939. The next prime is 15652340023. The reversal of 15652340021 is 12004325651.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6931395025 + 8720944996 = 83255^2 + 93386^2 .

It is a cyclic number.

It is not a de Polignac number, because 15652340021 - 2¹⁰ = 15652338997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15652340023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87934406 + ... + 87934583.

It is an arithmetic number, because the mean of its divisors is an integer number (3957052275).

Almost surely, 2^15652340021 is an apocalyptic number.

It is an amenable number.

15652340021 is a deficient number, since it is larger than the sum of its proper divisors (175869079).

15652340021 is an equidigital number, since it uses as much as digits as its factorization.

15652340021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175869078.

The product of its (nonzero) digits is 7200, while the sum is 29.

Adding to 15652340021 its reverse (12004325651), we get a palindrome (27656665672).

The spelling of 15652340021 in words is "fifteen billion, six hundred fifty-two million, three hundred forty thousand, twenty-one".