21241655121 has 12 divisors (see below), whose sum is σ = 28715518608. Its totient is φ = 13967105184.

The previous prime is 21241655107. The next prime is 21241655167. The reversal of 21241655121 is 12155614212.

It is not a de Polignac number, because 21241655121 - 2⁵ = 21241655089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21241655921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 648355 + ... + 680328.

It is an arithmetic number, because the mean of its divisors is an integer number (2392959884).

Almost surely, 2^21241655121 is an apocalyptic number.

It is an amenable number.

21241655121 is a deficient number, since it is larger than the sum of its proper divisors (7473863487).

21241655121 is an equidigital number, since it uses as much as digits as its factorization.

21241655121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1328832 (or 1328759 counting only the distinct ones).

The product of its digits is 4800, while the sum is 30.

The spelling of 21241655121 in words is "twenty-one billion, two hundred forty-one million, six hundred fifty-five thousand, one hundred twenty-one".