40478878642 has 4 divisors (see below), whose sum is σ = 60718317966. Its totient is φ = 20239439320.

The previous prime is 40478878637. The next prime is 40478878709. The reversal of 40478878642 is 24687887404.

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

It can be written as a sum of positive squares in only one way, i.e., 28890140841 + 11588737801 = 169971^2 + 107651^2 .

It is a super-2 number, since 2×40478878642² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10119719659 + ... + 10119719662.

Almost surely, 2^40478878642 is an apocalyptic number.

40478878642 is a deficient number, since it is larger than the sum of its proper divisors (20239439324).

40478878642 is a wasteful number, since it uses less digits than its factorization.

40478878642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20239439323.

The product of its (nonzero) digits is 19267584, while the sum is 58.

The spelling of 40478878642 in words is "forty billion, four hundred seventy-eight million, eight hundred seventy-eight thousand, six hundred forty-two".