81290255 has 4 divisors (see below), whose sum is σ = 97548312. Its totient is φ = 65032200.

The previous prime is 81290233. The next prime is 81290263. The reversal of 81290255 is 55209218.

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

It is not a de Polignac number, because 81290255 - 2¹⁰ = 81289231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8129021 + ... + 8129030.

It is an arithmetic number, because the mean of its divisors is an integer number (24387078).

Almost surely, 2^81290255 is an apocalyptic number.

81290255 is a deficient number, since it is larger than the sum of its proper divisors (16258057).

81290255 is a wasteful number, since it uses less digits than its factorization.

81290255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16258056.

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 81290255 is about 9016.1108577923. The cubic root of 81290255 is about 433.1910699996.

The spelling of 81290255 in words is "eighty-one million, two hundred ninety thousand, two hundred fifty-five".