661010465 has 4 divisors (see below), whose sum is σ = 793212564. Its totient is φ = 528808368.

The previous prime is 661010443. The next prime is 661010479. The reversal of 661010465 is 564010166.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 470542864 + 190467601 = 21692^2 + 13801^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661010465 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66101042 + ... + 66101051.

It is an arithmetic number, because the mean of its divisors is an integer number (198303141).

Almost surely, 2^661010465 is an apocalyptic number.

It is an amenable number.

661010465 is a deficient number, since it is larger than the sum of its proper divisors (132202099).

661010465 is a wasteful number, since it uses less digits than its factorization.

661010465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132202098.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 661010465 is about 25710.1237842217. The cubic root of 661010465 is about 871.1028709438.

The spelling of 661010465 in words is "six hundred sixty-one million, ten thousand, four hundred sixty-five".