81274875 has 128 divisors (see below), whose sum is σ = 167132160. Its totient is φ = 34560000.

The previous prime is 81274871. The next prime is 81274877. The reversal of 81274875 is 57847218.

81274875 is a nontrivial binomial coefficient, being equal to C(12750, 2).

It is not a de Polignac number, because 81274875 - 2² = 81274871 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81274871) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1332345 + ... + 1332405.

It is an arithmetic number, because the mean of its divisors is an integer number (1305720).

Almost surely, 2^81274875 is an apocalyptic number.

81274875 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

81274875 is the 12749-th triangular number and also the 6375-th hexagonal number.

81274875 is an abundant number, since it is smaller than the sum of its proper divisors (85857285).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81274875 is a wasteful number, since it uses less digits than its factorization.

81274875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126 (or 116 counting only the distinct ones).

The product of its digits is 125440, while the sum is 42.

The square root of 81274875 is about 9015.2578998052. The cubic root of 81274875 is about 433.1637485661.

The spelling of 81274875 in words is "eighty-one million, two hundred seventy-four thousand, eight hundred seventy-five".