1313121021 has 16 divisors (see below), whose sum is σ = 1857072384. Its totient is φ = 822472704.

The previous prime is 1313121011. The next prime is 1313121031. The reversal of 1313121021 is 1201213131.

It is a happy number.

1313121021 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1313121011) and next prime (1313121031).

It is not a de Polignac number, because 1313121021 - 2²⁹ = 776250109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1313121011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7116 + ... + 51738.

It is an arithmetic number, because the mean of its divisors is an integer number (116067024).

Almost surely, 2^1313121021 is an apocalyptic number.

It is an amenable number.

1313121021 is a deficient number, since it is larger than the sum of its proper divisors (543951363).

1313121021 is a wasteful number, since it uses less digits than its factorization.

1313121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45220.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1313121021 is about 36237.0117559382. The cubic root of 1313121021 is about 1095.0524417661.

Adding to 1313121021 its reverse (1201213131), we get a palindrome (2514334152).

The spelling of 1313121021 in words is "one billion, three hundred thirteen million, one hundred twenty-one thousand, twenty-one".