40199979 has 4 divisors (see below), whose sum is σ = 53599976. Its totient is φ = 26799984.

The previous prime is 40199977. The next prime is 40199981. The reversal of 40199979 is 97999104.

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

It is an interprime number because it is at equal distance from previous prime (40199977) and next prime (40199981).

It is not a de Polignac number, because 40199979 - 2¹ = 40199977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40199977) 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, 6699994 + ... + 6699999.

It is an arithmetic number, because the mean of its divisors is an integer number (13399994).

Almost surely, 2^40199979 is an apocalyptic number.

40199979 is a deficient number, since it is larger than the sum of its proper divisors (13399997).

40199979 is a wasteful number, since it uses less digits than its factorization.

40199979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13399996.

The product of its (nonzero) digits is 183708, while the sum is 48.

The square root of 40199979 is about 6340.3453375979. The cubic root of 40199979 is about 342.5641743105.

The spelling of 40199979 in words is "forty million, one hundred ninety-nine thousand, nine hundred seventy-nine".