11801556 has 72 divisors (see below), whose sum is σ = 32532864. Its totient is φ = 3585600.

The previous prime is 11801551. The next prime is 11801561. The reversal of 11801556 is 65510811.

It is an interprime number because it is at equal distance from previous prime (11801551) and next prime (11801561).

It is a super-2 number, since 2×11801556² = 278553448042272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11801551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70585 + ... + 70751.

Almost surely, 2^11801556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11801556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16266432).

11801556 is an abundant number, since it is smaller than the sum of its proper divisors (20731308).

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

11801556 is a wasteful number, since it uses less digits than its factorization.

11801556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341 (or 336 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 27.

The square root of 11801556 is about 3435.3392845540. The cubic root of 11801556 is about 227.6738179742.

The spelling of 11801556 in words is "eleven million, eight hundred one thousand, five hundred fifty-six".