11651521641 has 4 divisors (see below), whose sum is σ = 15535362192. Its totient is φ = 7767681092.

The previous prime is 11651521619. The next prime is 11651521663. The reversal of 11651521641 is 14612515611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (11651521619) and next prime (11651521663).

It is a cyclic number.

It is not a de Polignac number, because 11651521641 - 2⁶ = 11651521577 is a prime.

It is a super-3 number, since 3×11651521641³ (a number of 31 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (11651521681) 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, 1941920271 + ... + 1941920276.

It is an arithmetic number, because the mean of its divisors is an integer number (3883840548).

Almost surely, 2^11651521641 is an apocalyptic number.

It is an amenable number.

11651521641 is a deficient number, since it is larger than the sum of its proper divisors (3883840551).

11651521641 is an equidigital number, since it uses as much as digits as its factorization.

11651521641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3883840550.

The product of its digits is 7200, while the sum is 33.

The spelling of 11651521641 in words is "eleven billion, six hundred fifty-one million, five hundred twenty-one thousand, six hundred forty-one".