671861963 has 4 divisors (see below), whose sum is σ = 672294480. Its totient is φ = 671429448.

The previous prime is 671861959. The next prime is 671861987. The reversal of 671861963 is 369168176.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 671861963 - 2² = 671861959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671861923) 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, 213920 + ... + 217037.

It is an arithmetic number, because the mean of its divisors is an integer number (168073620).

Almost surely, 2^671861963 is an apocalyptic number.

671861963 is a deficient number, since it is larger than the sum of its proper divisors (432517).

671861963 is a wasteful number, since it uses less digits than its factorization.

671861963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432516.

The product of its digits is 326592, while the sum is 47.

The square root of 671861963 is about 25920.3002104528. The cubic root of 671861963 is about 875.8438500925.

The spelling of 671861963 in words is "six hundred seventy-one million, eight hundred sixty-one thousand, nine hundred sixty-three".