81201879 has 32 divisors (see below), whose sum is σ = 132583680. Its totient is φ = 48708000.

The previous prime is 81201863. The next prime is 81201907. The reversal of 81201879 is 97810218.

It is not a de Polignac number, because 81201879 - 2⁴ = 81201863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81201829) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28644 + ... + 31350.

It is an arithmetic number, because the mean of its divisors is an integer number (4143240).

Almost surely, 2^81201879 is an apocalyptic number.

81201879 is a deficient number, since it is larger than the sum of its proper divisors (51381801).

81201879 is a wasteful number, since it uses less digits than its factorization.

81201879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2828 (or 2822 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 81201879 is about 9011.2085205038. The cubic root of 81201879 is about 433.0340295443.

It can be divided in two parts, 8120 and 1879, that added together give a palindrome (9999).

The spelling of 81201879 in words is "eighty-one million, two hundred one thousand, eight hundred seventy-nine".