651109978117 has 2 divisors, whose sum is σ = 651109978118. Its totient is φ = 651109978116.

The previous prime is 651109978091. The next prime is 651109978121. The reversal of 651109978117 is 711879901156.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 615658360321 + 35451617796 = 784639^2 + 188286^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-651109978117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (651109978417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 325554989058 + 325554989059.

It is an arithmetic number, because the mean of its divisors is an integer number (325554989059).

Almost surely, 2^651109978117 is an apocalyptic number.

It is an amenable number.

651109978117 is a deficient number, since it is larger than the sum of its proper divisors (1).

651109978117 is an equidigital number, since it uses as much as digits as its factorization.

651109978117 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 952560, while the sum is 55.

The spelling of 651109978117 in words is "six hundred fifty-one billion, one hundred nine million, nine hundred seventy-eight thousand, one hundred seventeen".