561213749 has 4 divisors (see below), whose sum is σ = 569118240. Its totient is φ = 553309260.

The previous prime is 561213733. The next prime is 561213803. The reversal of 561213749 is 947312165.

561213749 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 561213749 - 2⁴ = 561213733 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 (561213349) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3952139 + ... + 3952280.

It is an arithmetic number, because the mean of its divisors is an integer number (142279560).

Almost surely, 2^561213749 is an apocalyptic number.

It is an amenable number.

561213749 is a deficient number, since it is larger than the sum of its proper divisors (7904491).

561213749 is an equidigital number, since it uses as much as digits as its factorization.

561213749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7904490.

The product of its digits is 45360, while the sum is 38.

The square root of 561213749 is about 23689.9503798552. The cubic root of 561213749 is about 824.8521309516.

The spelling of 561213749 in words is "five hundred sixty-one million, two hundred thirteen thousand, seven hundred forty-nine".