661075097 has 8 divisors (see below), whose sum is σ = 686213640. Its totient is φ = 636092800.

The previous prime is 661075091. The next prime is 661075099. The reversal of 661075097 is 790570166.

It can be written as a sum of positive squares in 4 ways, for example, as 276091456 + 384983641 = 16616^2 + 19621^2 .

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 661075097 - 2¹⁸ = 660812953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661075091) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30404 + ... + 47397.

It is an arithmetic number, because the mean of its divisors is an integer number (85776705).

Almost surely, 2^661075097 is an apocalyptic number.

It is an amenable number.

661075097 is a deficient number, since it is larger than the sum of its proper divisors (25138543).

661075097 is a wasteful number, since it uses less digits than its factorization.

661075097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78123.

The product of its (nonzero) digits is 79380, while the sum is 41.

The square root of 661075097 is about 25711.3806902702. The cubic root of 661075097 is about 871.1312614605.

The spelling of 661075097 in words is "six hundred sixty-one million, seventy-five thousand, ninety-seven".