71494887857 has 2 divisors, whose sum is σ = 71494887858. Its totient is φ = 71494887856.

The previous prime is 71494887847. The next prime is 71494887881. The reversal of 71494887857 is 75878849417.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38849986816 + 32644901041 = 197104^2 + 180679^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71494887857 is a prime.

It is a super-2 number, since 2×71494887857² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (71494887847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35747443928 + 35747443929.

It is an arithmetic number, because the mean of its divisors is an integer number (35747443929).

Almost surely, 2^71494887857 is an apocalyptic number.

It is an amenable number.

71494887857 is a deficient number, since it is larger than the sum of its proper divisors (1).

71494887857 is an equidigital number, since it uses as much as digits as its factorization.

71494887857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 126443520, while the sum is 68.

The spelling of 71494887857 in words is "seventy-one billion, four hundred ninety-four million, eight hundred eighty-seven thousand, eight hundred fifty-seven".