661010705 has 4 divisors (see below), whose sum is σ = 793212852. Its totient is φ = 528808560.

The previous prime is 661010687. The next prime is 661010719. The reversal of 661010705 is 507010166.

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 200307409 + 460703296 = 14153^2 + 21464^2 .

It is not a de Polignac number, because 661010705 - 2¹² = 661006609 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66101066 + ... + 66101075.

It is an arithmetic number, because the mean of its divisors is an integer number (198303213).

Almost surely, 2^661010705 is an apocalyptic number.

It is an amenable number.

661010705 is a deficient number, since it is larger than the sum of its proper divisors (132202147).

661010705 is a wasteful number, since it uses less digits than its factorization.

661010705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132202146.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 661010705 is about 25710.1284516433. The cubic root of 661010705 is about 871.1029763706.

The spelling of 661010705 in words is "six hundred sixty-one million, ten thousand, seven hundred five".