11644561123 has 4 divisors (see below), whose sum is σ = 12540296608. Its totient is φ = 10748825640.

The previous prime is 11644561109. The next prime is 11644561127. The reversal of 11644561123 is 32116544611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32116544611 = 251 ⋅127954361.

It is a cyclic number.

It is not a de Polignac number, because 11644561123 - 2⁹ = 11644560611 is a prime.

It is a super-2 number, since 2×11644561123² (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 (11644561127) 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, 447867723 + ... + 447867748.

It is an arithmetic number, because the mean of its divisors is an integer number (3135074152).

Almost surely, 2^11644561123 is an apocalyptic number.

11644561123 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

11644561123 is a deficient number, since it is larger than the sum of its proper divisors (895735485).

11644561123 is an equidigital number, since it uses as much as digits as its factorization.

11644561123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 895735484.

The product of its digits is 17280, while the sum is 34.

The spelling of 11644561123 in words is "eleven billion, six hundred forty-four million, five hundred sixty-one thousand, one hundred twenty-three".