40019879 has 4 divisors (see below), whose sum is σ = 40161576. Its totient is φ = 39878184.

The previous prime is 40019869. The next prime is 40019891. The reversal of 40019879 is 97891004.

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 40019879 - 2¹² = 40015783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40019809) 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, 70424 + ... + 70989.

It is an arithmetic number, because the mean of its divisors is an integer number (10040394).

Almost surely, 2^40019879 is an apocalyptic number.

40019879 is a deficient number, since it is larger than the sum of its proper divisors (141697).

40019879 is a wasteful number, since it uses less digits than its factorization.

40019879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141696.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 40019879 is about 6326.1266980673. The cubic root of 40019879 is about 342.0518343057.

The spelling of 40019879 in words is "forty million, nineteen thousand, eight hundred seventy-nine".