661601264 has 10 divisors (see below), whose sum is σ = 1281852480. Its totient is φ = 330800624.

The previous prime is 661601203. The next prime is 661601267. The reversal of 661601264 is 462106166.

It is a self number, because there is not a number n which added to its sum of digits gives 661601264.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661601267) 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 as a sum of consecutive naturals, namely, 20675024 + ... + 20675055.

It is an arithmetic number, because the mean of its divisors is an integer number (128185248).

Almost surely, 2^661601264 is an apocalyptic number.

It is an amenable number.

661601264 is a deficient number, since it is larger than the sum of its proper divisors (620251216).

661601264 is a wasteful number, since it uses less digits than its factorization.

661601264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41350087 (or 41350081 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 661601264 is about 25721.6108360266. The cubic root of 661601264 is about 871.3623189057.

The spelling of 661601264 in words is "six hundred sixty-one million, six hundred one thousand, two hundred sixty-four".