2153651215221 has 32 divisors (see below), whose sum is σ = 3663840460800. Its totient is φ = 1236546149040.

The previous prime is 2153651215189. The next prime is 2153651215223. The reversal of 2153651215221 is 1225121563512.

2153651215221 is a `hidden beast` number, since 2 + 1 + 5 + 3 + 6 + 5 + 121 + 522 + 1 = 666.

It is not a de Polignac number, because 2153651215221 - 2⁵ = 2153651215189 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2153651215223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 190819381 + ... + 190830666.

It is an arithmetic number, because the mean of its divisors is an integer number (114495014400).

Almost surely, 2^{2153651215221} is an apocalyptic number.

It is an amenable number.

2153651215221 is a deficient number, since it is larger than the sum of its proper divisors (1510189245579).

2153651215221 is a wasteful number, since it uses less digits than its factorization.

2153651215221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381650086 (or 381650080 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

Adding to 2153651215221 its reverse (1225121563512), we get a palindrome (3378772778733).

It can be divided in two parts, 215365 and 1215221, that added together give a triangular number (1430586 = T₁₆₉₁).

The spelling of 2153651215221 in words is "two trillion, one hundred fifty-three billion, six hundred fifty-one million, two hundred fifteen thousand, two hundred twenty-one".