1215713631 has 16 divisors (see below), whose sum is σ = 1769822208. Its totient is φ = 736166400.

The previous prime is 1215713581. The next prime is 1215713641. The reversal of 1215713631 is 1363175121.

It is not a de Polignac number, because 1215713631 - 2¹⁹ = 1215189343 is a prime.

It is a super-2 number, since 2×1215713631² = 2955919265198408322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215713641) 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, 25026 + ... + 55296.

It is an arithmetic number, because the mean of its divisors is an integer number (110613888).

Almost surely, 2^1215713631 is an apocalyptic number.

1215713631 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1215713631 is a deficient number, since it is larger than the sum of its proper divisors (554108577).

1215713631 is a wasteful number, since it uses less digits than its factorization.

1215713631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31502.

The product of its digits is 3780, while the sum is 30.

The square root of 1215713631 is about 34867.0852094063. The cubic root of 1215713631 is about 1067.2768648062.

Adding to 1215713631 its reverse (1363175121), we get a palindrome (2578888752).

The spelling of 1215713631 in words is "one billion, two hundred fifteen million, seven hundred thirteen thousand, six hundred thirty-one".