691740939 has 16 divisors (see below), whose sum is σ = 963673344. Its totient is φ = 440536800.

The previous prime is 691740911. The next prime is 691740941. The reversal of 691740939 is 939047196.

It is not a de Polignac number, because 691740939 - 2²⁰ = 690692363 is a prime.

It is not an unprimeable number, because it can be changed into a prime (691740979) 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, 50544 + ... + 62754.

It is an arithmetic number, because the mean of its divisors is an integer number (60229584).

Almost surely, 2^691740939 is an apocalyptic number.

691740939 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

691740939 is a deficient number, since it is larger than the sum of its proper divisors (271932405).

691740939 is a wasteful number, since it uses less digits than its factorization.

691740939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13058.

The product of its (nonzero) digits is 367416, while the sum is 48.

The square root of 691740939 is about 26300.9684042242. The cubic root of 691740939 is about 884.3981518809.

The spelling of 691740939 in words is "six hundred ninety-one million, seven hundred forty thousand, nine hundred thirty-nine".