82511971 has 4 divisors (see below), whose sum is σ = 86099472. Its totient is φ = 78924472.

The previous prime is 82511963. The next prime is 82511977. The reversal of 82511971 is 17911528.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 82511971 - 2³ = 82511963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82511977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1793716 + ... + 1793761.

It is an arithmetic number, because the mean of its divisors is an integer number (21524868).

Almost surely, 2^82511971 is an apocalyptic number.

82511971 is a deficient number, since it is larger than the sum of its proper divisors (3587501).

82511971 is a wasteful number, since it uses less digits than its factorization.

82511971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3587500.

The product of its digits is 5040, while the sum is 34.

The square root of 82511971 is about 9083.6100202508. The cubic root of 82511971 is about 435.3504394113.

The spelling of 82511971 in words is "eighty-two million, five hundred eleven thousand, nine hundred seventy-one".