3918778420 has 12 divisors (see below), whose sum is σ = 8229434724. Its totient is φ = 1567511360.

The previous prime is 3918778411. The next prime is 3918778429. The reversal of 3918778420 is 248778193.

It is an interprime number because it is at equal distance from previous prime (3918778411) and next prime (3918778429).

It can be written as a sum of positive squares in 2 ways, for example, as 801342864 + 3117435556 = 28308^2 + 55834^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3918778429) 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, 97969441 + ... + 97969480.

It is an arithmetic number, because the mean of its divisors is an integer number (685786227).

Almost surely, 2^3918778420 is an apocalyptic number.

It is an amenable number.

3918778420 is an abundant number, since it is smaller than the sum of its proper divisors (4310656304).

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

3918778420 is a wasteful number, since it uses less digits than its factorization.

3918778420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195938930 (or 195938928 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 49.

The square root of 3918778420 is about 62600.1471244278. The cubic root of 3918778420 is about 1576.5832296659.

The spelling of 3918778420 in words is "three billion, nine hundred eighteen million, seven hundred seventy-eight thousand, four hundred twenty".