561129551 has 16 divisors (see below), whose sum is σ = 596042496. Its totient is φ = 527172096.

The previous prime is 561129521. The next prime is 561129559. The reversal of 561129551 is 155921165.

It is a cyclic number.

It is not a de Polignac number, because 561129551 - 2²⁶ = 494020687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561129559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 367676 + ... + 369198.

It is an arithmetic number, because the mean of its divisors is an integer number (37252656).

Almost surely, 2^561129551 is an apocalyptic number.

561129551 is a deficient number, since it is larger than the sum of its proper divisors (34912945).

561129551 is a wasteful number, since it uses less digits than its factorization.

561129551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1822.

The product of its digits is 13500, while the sum is 35.

The square root of 561129551 is about 23688.1732305385. The cubic root of 561129551 is about 824.8108784737.

The spelling of 561129551 in words is "five hundred sixty-one million, one hundred twenty-nine thousand, five hundred fifty-one".