1644634897850 has 24 divisors (see below), whose sum is σ = 3496023897888. Its totient is φ = 563874822000.

The previous prime is 1644634897847. The next prime is 1644634897889. The reversal of 1644634897850 is 587984364461.

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, 2349478076 + ... + 2349478775.

It is an arithmetic number, because the mean of its divisors is an integer number (145667662412).

Almost surely, 2^{1644634897850} is an apocalyptic number.

1644634897850 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1644634897850 is an abundant number, since it is smaller than the sum of its proper divisors (1851389000038).

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

1644634897850 is a wasteful number, since it uses less digits than its factorization.

1644634897850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4698956870 (or 4698956865 counting only the distinct ones).

The product of its (nonzero) digits is 139345920, while the sum is 65.

The spelling of 1644634897850 in words is "one trillion, six hundred forty-four billion, six hundred thirty-four million, eight hundred ninety-seven thousand, eight hundred fifty".