11521540731 has 8 divisors (see below), whose sum is σ = 15362873344. Its totient is φ = 7680617640.

The previous prime is 11521540729. The next prime is 11521540763. The reversal of 11521540731 is 13704512511.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11521540731 - 2¹ = 11521540729 is a prime.

It is a super-2 number, since 2×11521540731² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11521540721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29275 + ... + 154596.

It is an arithmetic number, because the mean of its divisors is an integer number (1920359168).

Almost surely, 2^11521540731 is an apocalyptic number.

11521540731 is a deficient number, since it is larger than the sum of its proper divisors (3841332613).

11521540731 is a wasteful number, since it uses less digits than its factorization.

11521540731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204761.

The product of its (nonzero) digits is 4200, while the sum is 30.

The spelling of 11521540731 in words is "eleven billion, five hundred twenty-one million, five hundred forty thousand, seven hundred thirty-one".