81274851 has 12 divisors (see below), whose sum is σ = 134168112. Its totient is φ = 46442736.

The previous prime is 81274813. The next prime is 81274861. The reversal of 81274851 is 15847218.

It is not a de Polignac number, because 81274851 - 2¹⁷ = 81143779 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (81274861) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 644976 + ... + 645101.

It is an arithmetic number, because the mean of its divisors is an integer number (11180676).

Almost surely, 2^81274851 is an apocalyptic number.

81274851 is a deficient number, since it is larger than the sum of its proper divisors (52893261).

81274851 is a wasteful number, since it uses less digits than its factorization.

81274851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290090 (or 1290087 counting only the distinct ones).

The product of its digits is 17920, while the sum is 36.

The square root of 81274851 is about 9015.2565687284. The cubic root of 81274851 is about 433.1637059292.

The spelling of 81274851 in words is "eighty-one million, two hundred seventy-four thousand, eight hundred fifty-one".