1661025677 has 2 divisors, whose sum is σ = 1661025678. Its totient is φ = 1661025676.

The previous prime is 1661025599. The next prime is 1661025713. The reversal of 1661025677 is 7765201661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1659666121 + 1359556 = 40739^2 + 1166^2 .

It is a cyclic number.

It is not a de Polignac number, because 1661025677 - 2¹⁰ = 1661024653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661085677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830512838 + 830512839.

It is an arithmetic number, because the mean of its divisors is an integer number (830512839).

Almost surely, 2^1661025677 is an apocalyptic number.

It is an amenable number.

1661025677 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661025677 is an equidigital number, since it uses as much as digits as its factorization.

1661025677 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 105840, while the sum is 41.

The square root of 1661025677 is about 40755.6827571322. The cubic root of 1661025677 is about 1184.2919629867.

The spelling of 1661025677 in words is "one billion, six hundred sixty-one million, twenty-five thousand, six hundred seventy-seven".