197881279 has 2 divisors, whose sum is σ = 197881280. Its totient is φ = 197881278.

The previous prime is 197881247. The next prime is 197881283. The reversal of 197881279 is 972188791.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 197881279 - 2⁵ = 197881247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197881679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98940639 + 98940640.

It is an arithmetic number, because the mean of its divisors is an integer number (98940640).

Almost surely, 2^197881279 is an apocalyptic number.

197881279 is a deficient number, since it is larger than the sum of its proper divisors (1).

197881279 is an equidigital number, since it uses as much as digits as its factorization.

197881279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 52.

The square root of 197881279 is about 14067.0280798753. The cubic root of 197881279 is about 582.7311530176.

The spelling of 197881279 in words is "one hundred ninety-seven million, eight hundred eighty-one thousand, two hundred seventy-nine".