30139979 has 4 divisors (see below), whose sum is σ = 30150960. Its totient is φ = 30129000.

The previous prime is 30139957. The next prime is 30139981. The reversal of 30139979 is 97993103.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 30139979 - 2⁸ = 30139723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30139999) 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, 2729 + ... + 8229.

It is an arithmetic number, because the mean of its divisors is an integer number (7537740).

Almost surely, 2^30139979 is an apocalyptic number.

30139979 is a deficient number, since it is larger than the sum of its proper divisors (10981).

30139979 is an equidigital number, since it uses as much as digits as its factorization.

30139979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10980.

The product of its (nonzero) digits is 45927, while the sum is 41.

The square root of 30139979 is about 5489.9889799525. The cubic root of 30139979 is about 311.2057756664.

The spelling of 30139979 in words is "thirty million, one hundred thirty-nine thousand, nine hundred seventy-nine".