1381625857 has 2 divisors, whose sum is σ = 1381625858. Its totient is φ = 1381625856.

The previous prime is 1381625809. The next prime is 1381625867. The reversal of 1381625857 is 7585261831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1375593921 + 6031936 = 37089^2 + 2456^2 .

It is a cyclic number.

It is not a de Polignac number, because 1381625857 - 2¹⁹ = 1381101569 is a prime.

It is not a weakly prime, because it can be changed into another prime (1381625807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690812928 + 690812929.

It is an arithmetic number, because the mean of its divisors is an integer number (690812929).

Almost surely, 2^1381625857 is an apocalyptic number.

It is an amenable number.

1381625857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1381625857 is an equidigital number, since it uses as much as digits as its factorization.

1381625857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 403200, while the sum is 46.

The square root of 1381625857 is about 37170.2280999189. The cubic root of 1381625857 is about 1113.7733383279.

The spelling of 1381625857 in words is "one billion, three hundred eighty-one million, six hundred twenty-five thousand, eight hundred fifty-seven".