1378220640 has 48 divisors (see below), whose sum is σ = 4341396528. Its totient is φ = 367525376.

The previous prime is 1378220633. The next prime is 1378220663. The reversal of 1378220640 is 460228731.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1435167 + ... + 1436126.

It is an arithmetic number, because the mean of its divisors is an integer number (90445761).

Almost surely, 2^1378220640 is an apocalyptic number.

1378220640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1378220640 is an abundant number, since it is smaller than the sum of its proper divisors (2963175888).

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

1378220640 is a wasteful number, since it uses less digits than its factorization.

1378220640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2871311 (or 2871303 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 1378220640 is about 37124.3941364704. The cubic root of 1378220640 is about 1112.8575670051.

The spelling of 1378220640 in words is "one billion, three hundred seventy-eight million, two hundred twenty thousand, six hundred forty".