11644553440 has 48 divisors (see below), whose sum is σ = 29626436448. Its totient is φ = 4299526656.

The previous prime is 11644553407. The next prime is 11644553533. The reversal of 11644553440 is 4435544611.

It is a self number, because there is not a number n which added to its sum of digits gives 11644553440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2797092 + ... + 2801251.

It is an arithmetic number, because the mean of its divisors is an integer number (617217426).

Almost surely, 2^11644553440 is an apocalyptic number.

11644553440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11644553440 is an abundant number, since it is smaller than the sum of its proper divisors (17981883008).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11644553440 is a wasteful number, since it uses less digits than its factorization.

11644553440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5598371 (or 5598363 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 37.

The spelling of 11644553440 in words is "eleven billion, six hundred forty-four million, five hundred fifty-three thousand, four hundred forty".