197643390 has 32 divisors (see below), whose sum is σ = 542108160. Its totient is φ = 45175584.

The previous prime is 197643389. The next prime is 197643401. The reversal of 197643390 is 93346791.

It is a super-2 number, since 2×197643390² = 78125819221384200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

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, 470370 + ... + 470789.

It is an arithmetic number, because the mean of its divisors is an integer number (16940880).

Almost surely, 2^197643390 is an apocalyptic number.

197643390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

197643390 is an abundant number, since it is smaller than the sum of its proper divisors (344464770).

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

197643390 is a wasteful number, since it uses less digits than its factorization.

197643390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 941176.

The product of its (nonzero) digits is 122472, while the sum is 42.

The square root of 197643390 is about 14058.5699841769. The cubic root of 197643390 is about 582.4975433839.

The spelling of 197643390 in words is "one hundred ninety-seven million, six hundred forty-three thousand, three hundred ninety".