40388778 has 12 divisors (see below), whose sum is σ = 87509058. Its totient is φ = 13462920.

The previous prime is 40388767. The next prime is 40388779. The reversal of 40388778 is 87788304.

It can be written as a sum of positive squares in only one way, i.e., 39727809 + 660969 = 6303^2 + 813^2 .

It is not an unprimeable number, because it can be changed into a prime (40388779) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1121893 + ... + 1121928.

Almost surely, 2^40388778 is an apocalyptic number.

40388778 is an abundant number, since it is smaller than the sum of its proper divisors (47120280).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

40388778 is a wasteful number, since it uses less digits than its factorization.

40388778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2243829 (or 2243826 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 45.

The square root of 40388778 is about 6355.2165974104. The cubic root of 40388778 is about 343.0996205859.

The spelling of 40388778 in words is "forty million, three hundred eighty-eight thousand, seven hundred seventy-eight".