506705991 has 16 divisors (see below), whose sum is σ = 744329088. Its totient is φ = 304052000.

The previous prime is 506705977. The next prime is 506706043. The reversal of 506705991 is 199507605.

It is a cyclic number.

It is not a de Polignac number, because 506705991 - 2⁵ = 506705959 is a prime.

It is a super-2 number, since 2×506705991² = 513501922630584162, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (506705911) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72681 + ... + 79346.

It is an arithmetic number, because the mean of its divisors is an integer number (46520568).

Almost surely, 2^506705991 is an apocalyptic number.

506705991 is a deficient number, since it is larger than the sum of its proper divisors (237623097).

506705991 is a wasteful number, since it uses less digits than its factorization.

506705991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152142.

The product of its (nonzero) digits is 85050, while the sum is 42.

The square root of 506705991 is about 22510.1308525739. The cubic root of 506705991 is about 797.2331453219.

The spelling of 506705991 in words is "five hundred six million, seven hundred five thousand, nine hundred ninety-one".