971893257749 has 2 divisors, whose sum is σ = 971893257750. Its totient is φ = 971893257748.

The previous prime is 971893257689. The next prime is 971893257767. The reversal of 971893257749 is 947752398179.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 825950157124 + 145943100625 = 908818^2 + 382025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-971893257749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (971893257799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 485946628874 + 485946628875.

It is an arithmetic number, because the mean of its divisors is an integer number (485946628875).

Almost surely, 2^971893257749 is an apocalyptic number.

It is an amenable number.

971893257749 is a deficient number, since it is larger than the sum of its proper divisors (1).

971893257749 is an equidigital number, since it uses as much as digits as its factorization.

971893257749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 240045120, while the sum is 71.

The spelling of 971893257749 in words is "nine hundred seventy-one billion, eight hundred ninety-three million, two hundred fifty-seven thousand, seven hundred forty-nine".