197121870 has 128 divisors (see below), whose sum is σ = 592220160. Its totient is φ = 46224000.

The previous prime is 197121863. The next prime is 197121871. The reversal of 197121870 is 78121791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197121871) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 91000 + ... + 93140.

It is an arithmetic number, because the mean of its divisors is an integer number (4626720).

Almost surely, 2^197121870 is an apocalyptic number.

197121870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 197121870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (296110080).

197121870 is an abundant number, since it is smaller than the sum of its proper divisors (395098290).

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

197121870 is a wasteful number, since it uses less digits than its factorization.

197121870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2199 (or 2193 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 36.

The square root of 197121870 is about 14040.0096153813. The cubic root of 197121870 is about 581.9847482452.

The spelling of 197121870 in words is "one hundred ninety-seven million, one hundred twenty-one thousand, eight hundred seventy".