81964916271 has 48 divisors (see below), whose sum is σ = 145694764800. Its totient is φ = 43334786304.

The previous prime is 81964916269. The next prime is 81964916273. The reversal of 81964916271 is 17261946918.

81964916271 is a `hidden beast` number, since 8 + 1 + 9 + 6 + 4 + 9 + 1 + 627 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (81964916269) and next prime (81964916273).

It is not a de Polignac number, because 81964916271 - 2¹ = 81964916269 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81964916273) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 585381 + ... + 711758.

It is an arithmetic number, because the mean of its divisors is an integer number (3035307600).

Almost surely, 2^81964916271 is an apocalyptic number.

81964916271 is a deficient number, since it is larger than the sum of its proper divisors (63729848529).

81964916271 is a wasteful number, since it uses less digits than its factorization.

81964916271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1297228 (or 1297225 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 54.

The spelling of 81964916271 in words is "eighty-one billion, nine hundred sixty-four million, nine hundred sixteen thousand, two hundred seventy-one".