668451261 has 8 divisors (see below), whose sum is σ = 893337984. Its totient is φ = 444599360.

The previous prime is 668451257. The next prime is 668451263. The reversal of 668451261 is 162154866.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 668451261 - 2² = 668451257 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668451263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 257196 + ... + 259781.

It is an arithmetic number, because the mean of its divisors is an integer number (111667248).

Almost surely, 2^668451261 is an apocalyptic number.

It is an amenable number.

668451261 is a deficient number, since it is larger than the sum of its proper divisors (224886723).

668451261 is a wasteful number, since it uses less digits than its factorization.

668451261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 517411.

The product of its digits is 69120, while the sum is 39.

The square root of 668451261 is about 25854.4243989303. The cubic root of 668451261 is about 874.3592636026.

The spelling of 668451261 in words is "six hundred sixty-eight million, four hundred fifty-one thousand, two hundred sixty-one".