661380854 has 8 divisors (see below), whose sum is σ = 996404160. Its totient is φ = 329246136.

The previous prime is 661380817. The next prime is 661380859. The reversal of 661380854 is 458083166.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661380859) 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, 721574 + ... + 722489.

It is an arithmetic number, because the mean of its divisors is an integer number (124550520).

Almost surely, 2^661380854 is an apocalyptic number.

661380854 is a deficient number, since it is larger than the sum of its proper divisors (335023306).

661380854 is a wasteful number, since it uses less digits than its factorization.

661380854 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1444294.

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 661380854 is about 25717.3259496395. The cubic root of 661380854 is about 871.2655444532.

The spelling of 661380854 in words is "six hundred sixty-one million, three hundred eighty thousand, eight hundred fifty-four".