3878402640 has 80 divisors (see below), whose sum is σ = 13740632448. Its totient is φ = 886491648.

The previous prime is 3878402629. The next prime is 3878402651. The reversal of 3878402640 is 462048783.

It is an interprime number because it is at equal distance from previous prime (3878402629) and next prime (3878402651).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 3878402592 and 3878402601.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1152607 + ... + 1155966.

Almost surely, 2^3878402640 is an apocalyptic number.

3878402640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

3878402640 is an abundant number, since it is smaller than the sum of its proper divisors (9862229808).

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

3878402640 is a wasteful number, since it uses less digits than its factorization.

3878402640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2308596 (or 2308590 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 42.

The square root of 3878402640 is about 62276.8226549814. The cubic root of 3878402640 is about 1571.1499330912.

The spelling of 3878402640 in words is "three billion, eight hundred seventy-eight million, four hundred two thousand, six hundred forty".