15452551221 has 4 divisors (see below), whose sum is σ = 20603401632. Its totient is φ = 10301700812.

The previous prime is 15452551193. The next prime is 15452551229. The reversal of 15452551221 is 12215525451.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12215525451 = 3 ⋅4071841817.

It is a cyclic number.

It is not a de Polignac number, because 15452551221 - 2²⁷ = 15318333493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15452551229) 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, 2575425201 + ... + 2575425206.

It is an arithmetic number, because the mean of its divisors is an integer number (5150850408).

Almost surely, 2^15452551221 is an apocalyptic number.

It is an amenable number.

15452551221 is a deficient number, since it is larger than the sum of its proper divisors (5150850411).

15452551221 is an equidigital number, since it uses as much as digits as its factorization.

15452551221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5150850410.

The product of its digits is 20000, while the sum is 33.

The spelling of 15452551221 in words is "fifteen billion, four hundred fifty-two million, five hundred fifty-one thousand, two hundred twenty-one".