1013615621 has 4 divisors (see below), whose sum is σ = 1015259052. Its totient is φ = 1011972192.

The previous prime is 1013615593. The next prime is 1013615623. The reversal of 1013615621 is 1265163101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1265163101 = 1381 ⋅916121.

It can be written as a sum of positive squares in 2 ways, for example, as 39551521 + 974064100 = 6289^2 + 31210^2 .

It is a cyclic number.

It is not a de Polignac number, because 1013615621 - 2¹⁸ = 1013353477 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 (1013615623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 820790 + ... + 822023.

It is an arithmetic number, because the mean of its divisors is an integer number (253814763).

Almost surely, 2^1013615621 is an apocalyptic number.

It is an amenable number.

1013615621 is a deficient number, since it is larger than the sum of its proper divisors (1643431).

1013615621 is an equidigital number, since it uses as much as digits as its factorization.

1013615621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643430.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 1013615621 is about 31837.3306198871. The cubic root of 1013615621 is about 1004.5180963954.

Adding to 1013615621 its reverse (1265163101), we get a palindrome (2278778722).

The spelling of 1013615621 in words is "one billion, thirteen million, six hundred fifteen thousand, six hundred twenty-one".