402979 has 4 divisors (see below), whose sum is σ = 408160. Its totient is φ = 397800.

The previous prime is 402949. The next prime is 402991. The reversal of 402979 is 979204.

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 402979 - 2⁵ = 402947 is a prime.

It is an Ulam number.

It is a Duffinian number.

402979 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 402979.

It is not an unprimeable number, because it can be changed into a prime (402949) 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, 2472 + ... + 2629.

It is an arithmetic number, because the mean of its divisors is an integer number (102040).

2⁴⁰²⁹⁷⁹ is an apocalyptic number.

402979 is a deficient number, since it is larger than the sum of its proper divisors (5181).

402979 is an equidigital number, since it uses as much as digits as its factorization.

402979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5180.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 402979 is about 634.8062696603. The cubic root of 402979 is about 73.8630899267.

The spelling of 402979 in words is "four hundred two thousand, nine hundred seventy-nine".