661333268 has 6 divisors (see below), whose sum is σ = 1157333226. Its totient is φ = 330666632.

The previous prime is 661333241. The next prime is 661333273. The reversal of 661333268 is 862333166.

It can be written as a sum of positive squares in only one way, i.e., 454030864 + 207302404 = 21308^2 + 14398^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82666655 + ... + 82666662.

It is an arithmetic number, because the mean of its divisors is an integer number (192888871).

Almost surely, 2^661333268 is an apocalyptic number.

It is an amenable number.

661333268 is a deficient number, since it is larger than the sum of its proper divisors (495999958).

661333268 is a wasteful number, since it uses less digits than its factorization.

661333268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165333321 (or 165333319 counting only the distinct ones).

The product of its digits is 93312, while the sum is 38.

The square root of 661333268 is about 25716.4007590487. The cubic root of 661333268 is about 871.2446482548.

The spelling of 661333268 in words is "six hundred sixty-one million, three hundred thirty-three thousand, two hundred sixty-eight".