1878992640 has 432 divisors, whose sum is σ = 7713957888. Its totient is φ = 428986368.

The previous prime is 1878992627. The next prime is 1878992681. The reversal of 1878992640 is 462998781.

It is a tau number, because it is divible by the number of its divisors (432).

It is a super-2 number, since 2×1878992640² = 7061226682348339200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2176849 + ... + 2177711.

It is an arithmetic number, because the mean of its divisors is an integer number (17856384).

Almost surely, 2^1878992640 is an apocalyptic number.

1878992640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1878992640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3856978944).

1878992640 is an abundant number, since it is smaller than the sum of its proper divisors (5834965248).

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

1878992640 is an frugal number, since it uses more digits than its factorization.

1878992640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906 (or 880 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The square root of 1878992640 is about 43347.3487078506. The cubic root of 1878992640 is about 1233.9806785893.

The spelling of 1878992640 in words is "one billion, eight hundred seventy-eight million, nine hundred ninety-two thousand, six hundred forty".