1257660101 has 2 divisors, whose sum is σ = 1257660102. Its totient is φ = 1257660100.

The previous prime is 1257660077. The next prime is 1257660109. The reversal of 1257660101 is 1010667521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 997612225 + 260047876 = 31585^2 + 16126^2 .

It is an emirp because it is prime and its reverse (1010667521) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1257660101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1257660109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628830050 + 628830051.

It is an arithmetic number, because the mean of its divisors is an integer number (628830051).

Almost surely, 2^1257660101 is an apocalyptic number.

It is an amenable number.

1257660101 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257660101 is an equidigital number, since it uses as much as digits as its factorization.

1257660101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 1257660101 is about 35463.5037891069. The cubic root of 1257660101 is about 1079.4132904386.

The spelling of 1257660101 in words is "one billion, two hundred fifty-seven million, six hundred sixty thousand, one hundred one".