690979 has 4 divisors (see below), whose sum is σ = 693720. Its totient is φ = 688240.

The previous prime is 690953. The next prime is 690997. The reversal of 690979 is 979096.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 690979 - 2⁹ = 690467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (690919) 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, 949 + ... + 1510.

It is an arithmetic number, because the mean of its divisors is an integer number (173430).

2⁶⁹⁰⁹⁷⁹ is an apocalyptic number.

690979 is a deficient number, since it is larger than the sum of its proper divisors (2741).

690979 is a wasteful number, since it uses less digits than its factorization.

690979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2740.

The product of its (nonzero) digits is 30618, while the sum is 40.

The square root of 690979 is about 831.2514661641. The cubic root of 690979 is about 88.4073316879.

The spelling of 690979 in words is "six hundred ninety thousand, nine hundred seventy-nine".