21152513149 has 4 divisors (see below), whose sum is σ = 21420266560. Its totient is φ = 20884759740.

The previous prime is 21152513141. The next prime is 21152513153. The reversal of 21152513149 is 94131525112.

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.

It is a cyclic number.

It is not a de Polignac number, because 21152513149 - 2³ = 21152513141 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 (21152513141) 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, 133876587 + ... + 133876744.

It is an arithmetic number, because the mean of its divisors is an integer number (5355066640).

Almost surely, 2^21152513149 is an apocalyptic number.

It is an amenable number.

21152513149 is a deficient number, since it is larger than the sum of its proper divisors (267753411).

21152513149 is an equidigital number, since it uses as much as digits as its factorization.

21152513149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267753410.

The product of its digits is 10800, while the sum is 34.

The spelling of 21152513149 in words is "twenty-one billion, one hundred fifty-two million, five hundred thirteen thousand, one hundred forty-nine".