82971778 has 4 divisors (see below), whose sum is σ = 124457670. Its totient is φ = 41485888.

The previous prime is 82971769. The next prime is 82971793. The reversal of 82971778 is 87717928.

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

It can be written as a sum of positive squares in only one way, i.e., 45603009 + 37368769 = 6753^2 + 6113^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20742943 + ... + 20742946.

Almost surely, 2^82971778 is an apocalyptic number.

82971778 is a deficient number, since it is larger than the sum of its proper divisors (41485892).

82971778 is a wasteful number, since it uses less digits than its factorization.

82971778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41485891.

The product of its digits is 395136, while the sum is 49.

The square root of 82971778 is about 9108.8845639848. The cubic root of 82971778 is about 436.1576212362.

The spelling of 82971778 in words is "eighty-two million, nine hundred seventy-one thousand, seven hundred seventy-eight".