2139979 has 2 divisors, whose sum is σ = 2139980. Its totient is φ = 2139978.

The previous prime is 2139967. The next prime is 2140001. The reversal of 2139979 is 9799312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2139979 - 2⁵ = 2139947 is a prime.

It is not a weakly prime, because it can be changed into another prime (2139919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1069989 + 1069990.

It is an arithmetic number, because the mean of its divisors is an integer number (1069990).

2^2139979 is an apocalyptic number.

2139979 is a deficient number, since it is larger than the sum of its proper divisors (1).

2139979 is an equidigital number, since it uses as much as digits as its factorization.

2139979 is an evil number, because the sum of its binary digits is even.

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

The square root of 2139979 is about 1462.8667061629. The cubic root of 2139979 is about 128.8654527289.

It can be divided in two parts, 2139 and 979, that multiplied together give a triangular number (2094081 = T₂₀₄₆).

The spelling of 2139979 in words is "two million, one hundred thirty-nine thousand, nine hundred seventy-nine".