81877801 has 4 divisors (see below), whose sum is σ = 81978112. Its totient is φ = 81777492.

The previous prime is 81877793. The next prime is 81877813. The reversal of 81877801 is 10877818.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81877801 - 2³ = 81877793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81877841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48921 + ... + 50566.

It is an arithmetic number, because the mean of its divisors is an integer number (20494528).

Almost surely, 2^81877801 is an apocalyptic number.

It is an amenable number.

81877801 is a deficient number, since it is larger than the sum of its proper divisors (100311).

81877801 is an equidigital number, since it uses as much as digits as its factorization.

81877801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100310.

The product of its (nonzero) digits is 25088, while the sum is 40.

The square root of 81877801 is about 9048.6353114710. The cubic root of 81877801 is about 434.2322318173.

The spelling of 81877801 in words is "eighty-one million, eight hundred seventy-seven thousand, eight hundred one".