197991426 has 8 divisors (see below), whose sum is σ = 395982864. Its totient is φ = 65997140.

The previous prime is 197991413. The next prime is 197991427. The reversal of 197991426 is 624199791.

It is a sphenic number, since it is the product of 3 distinct primes.

197991426 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (197991427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16499280 + ... + 16499291.

It is an arithmetic number, because the mean of its divisors is an integer number (49497858).

Almost surely, 2^197991426 is an apocalyptic number.

197991426 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

197991426 is a wasteful number, since it uses less digits than its factorization.

197991426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32998576.

The product of its digits is 244944, while the sum is 48.

The square root of 197991426 is about 14070.9426123483. The cubic root of 197991426 is about 582.8392551803.

The spelling of 197991426 in words is "one hundred ninety-seven million, nine hundred ninety-one thousand, four hundred twenty-six".