641263191 has 8 divisors (see below), whose sum is σ = 855283440. Its totient is φ = 427375872.

The previous prime is 641263187. The next prime is 641263199. The reversal of 641263191 is 191362146.

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

It is not a de Polignac number, because 641263191 - 2² = 641263187 is a prime.

It is a super-2 number, since 2×641263191² = 822436960263004962, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641263199) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21370 + ... + 41703.

It is an arithmetic number, because the mean of its divisors is an integer number (106910430).

Almost surely, 2^641263191 is an apocalyptic number.

641263191 is a deficient number, since it is larger than the sum of its proper divisors (214020249).

641263191 is a wasteful number, since it uses less digits than its factorization.

641263191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66465.

The product of its digits is 7776, while the sum is 33.

The square root of 641263191 is about 25323.1749786633. The cubic root of 641263191 is about 862.3404747604.

It can be divided in two parts, 64 and 1263191, that added together give a triangular number (1263255 = T₁₅₈₉).

The spelling of 641263191 in words is "six hundred forty-one million, two hundred sixty-three thousand, one hundred ninety-one".