11561031 has 6 divisors (see below), whose sum is σ = 16699280. Its totient is φ = 7707348.

The previous prime is 11561027. The next prime is 11561087. The reversal of 11561031 is 13016511.

It is not a de Polignac number, because 11561031 - 2² = 11561027 is a prime.

It is a super-2 number, since 2×11561031² = 267314875565922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11560995 and 11561013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11561021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 642271 + ... + 642288.

Almost surely, 2^11561031 is an apocalyptic number.

11561031 is a deficient number, since it is larger than the sum of its proper divisors (5138249).

11561031 is a wasteful number, since it uses less digits than its factorization.

11561031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1284565 (or 1284562 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 18.

The square root of 11561031 is about 3400.1516142666. The cubic root of 11561031 is about 226.1164656711.

Adding to 11561031 its reverse (13016511), we get a palindrome (24577542).

It can be divided in two parts, 1156 and 1031, that added together give a 7-th power (2187 = 3⁷).

The spelling of 11561031 in words is "eleven million, five hundred sixty-one thousand, thirty-one".