1997645570 has 32 divisors (see below), whose sum is σ = 3727149120. Its totient is φ = 769970880.

The previous prime is 1997645491. The next prime is 1997645597. The reversal of 1997645570 is 755467991.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145085 + ... + 158255.

It is an arithmetic number, because the mean of its divisors is an integer number (116473410).

Almost surely, 2^1997645570 is an apocalyptic number.

1997645570 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1997645570 is a deficient number, since it is larger than the sum of its proper divisors (1729503550).

1997645570 is a wasteful number, since it uses less digits than its factorization.

1997645570 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13730.

The product of its (nonzero) digits is 2381400, while the sum is 53.

The square root of 1997645570 is about 44695.0284707371. The cubic root of 1997645570 is about 1259.4264564435.

The spelling of 1997645570 in words is "one billion, nine hundred ninety-seven million, six hundred forty-five thousand, five hundred seventy".