81379876 has 6 divisors (see below), whose sum is σ = 142414790. Its totient is φ = 40689936.

The previous prime is 81379873. The next prime is 81379877. The reversal of 81379876 is 67897318.

It can be written as a sum of positive squares in only one way, i.e., 70157376 + 11222500 = 8376^2 + 3350^2 .

It is not an unprimeable number, because it can be changed into a prime (81379873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10172481 + ... + 10172488.

Almost surely, 2^81379876 is an apocalyptic number.

It is an amenable number.

81379876 is a deficient number, since it is larger than the sum of its proper divisors (61034914).

81379876 is a wasteful number, since it uses less digits than its factorization.

81379876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20344973 (or 20344971 counting only the distinct ones).

The product of its digits is 508032, while the sum is 49.

The square root of 81379876 is about 9021.0795362861. The cubic root of 81379876 is about 433.3502065751.

The spelling of 81379876 in words is "eighty-one million, three hundred seventy-nine thousand, eight hundred seventy-six".