1265166601 has 2 divisors, whose sum is σ = 1265166602. Its totient is φ = 1265166600.

The previous prime is 1265166587. The next prime is 1265166611. The reversal of 1265166601 is 1066615621.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1160083600 + 105083001 = 34060^2 + 10251^2 .

It is a cyclic number.

It is not a de Polignac number, because 1265166601 - 2²³ = 1256777993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1265166611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632583300 + 632583301.

It is an arithmetic number, because the mean of its divisors is an integer number (632583301).

Almost surely, 2^1265166601 is an apocalyptic number.

It is an amenable number.

1265166601 is a deficient number, since it is larger than the sum of its proper divisors (1).

1265166601 is an equidigital number, since it uses as much as digits as its factorization.

1265166601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 1265166601 is about 35569.1804937927. The cubic root of 1265166601 is about 1081.5565692180.

The spelling of 1265166601 in words is "one billion, two hundred sixty-five million, one hundred sixty-six thousand, six hundred one".