641591194 has 4 divisors (see below), whose sum is σ = 962386794. Its totient is φ = 320795596.

The previous prime is 641591189. The next prime is 641591201. The reversal of 641591194 is 491195146.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 638825625 + 2765569 = 25275^2 + 1663^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160397797 + ... + 160397800.

Almost surely, 2^641591194 is an apocalyptic number.

641591194 is a deficient number, since it is larger than the sum of its proper divisors (320795600).

641591194 is a wasteful number, since it uses less digits than its factorization.

641591194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320795599.

The product of its digits is 38880, while the sum is 40.

The square root of 641591194 is about 25329.6504910747. The cubic root of 641591194 is about 862.4874773509.

The spelling of 641591194 in words is "six hundred forty-one million, five hundred ninety-one thousand, one hundred ninety-four".