661095863 has 4 divisors (see below), whose sum is σ = 682421568. Its totient is φ = 639770160.

The previous prime is 661095859. The next prime is 661095887. The reversal of 661095863 is 368590166.

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 661095863 - 2² = 661095859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661095893) 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, 10662806 + ... + 10662867.

It is an arithmetic number, because the mean of its divisors is an integer number (170605392).

Almost surely, 2^661095863 is an apocalyptic number.

661095863 is a deficient number, since it is larger than the sum of its proper divisors (21325705).

661095863 is a wasteful number, since it uses less digits than its factorization.

661095863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21325704.

The product of its (nonzero) digits is 233280, while the sum is 44.

The square root of 661095863 is about 25711.7845160541. The cubic root of 661095863 is about 871.1403828258.

The spelling of 661095863 in words is "six hundred sixty-one million, ninety-five thousand, eight hundred sixty-three".