81946977 has 8 divisors (see below), whose sum is σ = 124871616. Its totient is φ = 46826832.

The previous prime is 81946967. The next prime is 81947009. The reversal of 81946977 is 77964918.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81946977 - 2¹² = 81942881 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81946927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1951098 + ... + 1951139.

It is an arithmetic number, because the mean of its divisors is an integer number (15608952).

Almost surely, 2^81946977 is an apocalyptic number.

It is an amenable number.

81946977 is a deficient number, since it is larger than the sum of its proper divisors (42924639).

81946977 is a wasteful number, since it uses less digits than its factorization.

81946977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3902247.

The product of its digits is 762048, while the sum is 51.

The square root of 81946977 is about 9052.4569593012. The cubic root of 81946977 is about 434.3544871496.

The spelling of 81946977 in words is "eighty-one million, nine hundred forty-six thousand, nine hundred seventy-seven".