774405661 has 2 divisors, whose sum is σ = 774405662. Its totient is φ = 774405660.

The previous prime is 774405623. The next prime is 774405677. The reversal of 774405661 is 166504477.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 480968761 + 293436900 = 21931^2 + 17130^2 .

It is a cyclic number.

It is not a de Polignac number, because 774405661 - 2¹⁹ = 773881373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (774403661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 387202830 + 387202831.

It is an arithmetic number, because the mean of its divisors is an integer number (387202831).

Almost surely, 2^774405661 is an apocalyptic number.

It is an amenable number.

774405661 is a deficient number, since it is larger than the sum of its proper divisors (1).

774405661 is an equidigital number, since it uses as much as digits as its factorization.

774405661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 141120, while the sum is 40.

The square root of 774405661 is about 27828.1451232381. The cubic root of 774405661 is about 918.3104075254.

The spelling of 774405661 in words is "seven hundred seventy-four million, four hundred five thousand, six hundred sixty-one".