1878281640 has 48 divisors (see below), whose sum is σ = 6104416500. Its totient is φ = 500875008.

The previous prime is 1878281623. The next prime is 1878281687. The reversal of 1878281640 is 461828781.

It can be written as a sum of positive squares in 2 ways, for example, as 1875063204 + 3218436 = 43302^2 + 1794^2 .

It is a super-2 number, since 2×1878281640² = 7055883838322179200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2608365 + ... + 2609084.

Almost surely, 2^1878281640 is an apocalyptic number.

1878281640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1878281640 is an abundant number, since it is smaller than the sum of its proper divisors (4226134860).

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

1878281640 is a wasteful number, since it uses less digits than its factorization.

1878281640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5217466 (or 5217459 counting only the distinct ones).

The product of its (nonzero) digits is 172032, while the sum is 45.

The square root of 1878281640 is about 43339.1467382550. The cubic root of 1878281640 is about 1233.8250152249.

The spelling of 1878281640 in words is "one billion, eight hundred seventy-eight million, two hundred eighty-one thousand, six hundred forty".