81616051202687 has 2 divisors, whose sum is σ = 81616051202688. Its totient is φ = 81616051202686.

The previous prime is 81616051202639. The next prime is 81616051202729. The reversal of 81616051202687 is 78620215061618.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81616051202687 - 2¹⁴ = 81616051186303 is a prime.

It is a super-2 number, since 2×81616051202687² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81616051282687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40808025601343 + 40808025601344.

It is an arithmetic number, because the mean of its divisors is an integer number (40808025601344).

Almost surely, 2^{81616051202687} is an apocalyptic number.

81616051202687 is a deficient number, since it is larger than the sum of its proper divisors (1).

81616051202687 is an equidigital number, since it uses as much as digits as its factorization.

81616051202687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1935360, while the sum is 53.

The spelling of 81616051202687 in words is "eighty-one trillion, six hundred sixteen billion, fifty-one million, two hundred two thousand, six hundred eighty-seven".