661774093 has 2 divisors, whose sum is σ = 661774094. Its totient is φ = 661774092.

The previous prime is 661774067. The next prime is 661774103. The reversal of 661774093 is 390477166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 409536169 + 252237924 = 20237^2 + 15882^2 .

It is a cyclic number.

It is not a de Polignac number, because 661774093 - 2²⁵ = 628219661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661774493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330887046 + 330887047.

It is an arithmetic number, because the mean of its divisors is an integer number (330887047).

Almost surely, 2^661774093 is an apocalyptic number.

It is an amenable number.

661774093 is a deficient number, since it is larger than the sum of its proper divisors (1).

661774093 is an equidigital number, since it uses as much as digits as its factorization.

661774093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 190512, while the sum is 43.

The square root of 661774093 is about 25724.9702235007. The cubic root of 661774093 is about 871.4381871439.

The spelling of 661774093 in words is "six hundred sixty-one million, seven hundred seventy-four thousand, ninety-three".