11540721631 has 4 divisors (see below), whose sum is σ = 11543893192. Its totient is φ = 11537550072.

The previous prime is 11540721611. The next prime is 11540721683. The reversal of 11540721631 is 13612704511.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11540721631 - 2⁷ = 11540721503 is a prime.

It is a super-2 number, since 2×11540721631² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11540721593 and 11540721602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11540721601) 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, 1580316 + ... + 1587601.

It is an arithmetic number, because the mean of its divisors is an integer number (2885973298).

Almost surely, 2^11540721631 is an apocalyptic number.

11540721631 is a deficient number, since it is larger than the sum of its proper divisors (3171561).

11540721631 is an equidigital number, since it uses as much as digits as its factorization.

11540721631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3171560.

The product of its (nonzero) digits is 5040, while the sum is 31.

The spelling of 11540721631 in words is "eleven billion, five hundred forty million, seven hundred twenty-one thousand, six hundred thirty-one".