1897568640 has 512 divisors, whose sum is σ = 7490880000. Its totient is φ = 450109440.

The previous prime is 1897568633. The next prime is 1897568671. The reversal of 1897568640 is 468657981.

1897568640 is a `hidden beast` number, since 18 + 9 + 7 + 568 + 64 + 0 = 666.

It is a super-2 number, since 2×1897568640² = 7201533487022899200, 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 63 ways as a sum of consecutive naturals, for example, 12735286 + ... + 12735434.

It is an arithmetic number, because the mean of its divisors is an integer number (14630625).

Almost surely, 2^1897568640 is an apocalyptic number.

1897568640 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 1897568640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3745440000).

1897568640 is an abundant number, since it is smaller than the sum of its proper divisors (5593311360).

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

1897568640 is a wasteful number, since it uses less digits than its factorization.

1897568640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255 (or 237 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The square root of 1897568640 is about 43561.0908954310. The cubic root of 1897568640 is about 1238.0337899211.

The spelling of 1897568640 in words is "one billion, eight hundred ninety-seven million, five hundred sixty-eight thousand, six hundred forty".