561749139 has 24 divisors (see below), whose sum is σ = 981882720. Its totient is φ = 302116608.

The previous prime is 561749131. The next prime is 561749147. The reversal of 561749139 is 931947165.

561749139 is a `hidden beast` number, since 561 + 74 + 9 + 13 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (561749131) and next prime (561749147).

It is not a de Polignac number, because 561749139 - 2³ = 561749131 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 561749094 and 561749103.

It is not an unprimeable number, because it can be changed into a prime (561749131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 261184 + ... + 263325.

It is an arithmetic number, because the mean of its divisors is an integer number (40911780).

Almost surely, 2^561749139 is an apocalyptic number.

561749139 is a deficient number, since it is larger than the sum of its proper divisors (420133581).

561749139 is a wasteful number, since it uses less digits than its factorization.

561749139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 524539 (or 524536 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 561749139 is about 23701.2476253888. The cubic root of 561749139 is about 825.1143466850.

It can be divided in two parts, 5617 and 49139, that added together give a square (54756 = 234²).

The spelling of 561749139 in words is "five hundred sixty-one million, seven hundred forty-nine thousand, one hundred thirty-nine".