11801280561 has 64 divisors (see below), whose sum is σ = 18923520000. Its totient is φ = 6399896832.

The previous prime is 11801280523. The next prime is 11801280581. The reversal of 11801280561 is 16508210811.

It is not a de Polignac number, because 11801280561 - 2³⁰ = 10727538737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11801280511) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9226320 + ... + 9227598.

It is an arithmetic number, because the mean of its divisors is an integer number (295680000).

Almost surely, 2^11801280561 is an apocalyptic number.

It is an amenable number.

11801280561 is a deficient number, since it is larger than the sum of its proper divisors (7122239439).

11801280561 is a wasteful number, since it uses less digits than its factorization.

11801280561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1566.

The product of its (nonzero) digits is 3840, while the sum is 33.

The spelling of 11801280561 in words is "eleven billion, eight hundred one million, two hundred eighty thousand, five hundred sixty-one".