81672851 has 8 divisors (see below), whose sum is σ = 88404624. Its totient is φ = 75005280.

The previous prime is 81672823. The next prime is 81672863. The reversal of 81672851 is 15827618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81672851 - 2¹⁴ = 81656467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81672821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13385 + ... + 18506.

It is an arithmetic number, because the mean of its divisors is an integer number (11050578).

Almost surely, 2^81672851 is an apocalyptic number.

81672851 is a deficient number, since it is larger than the sum of its proper divisors (6731773).

81672851 is a wasteful number, since it uses less digits than its factorization.

81672851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32101.

The product of its digits is 26880, while the sum is 38.

The square root of 81672851 is about 9037.3033035303. The cubic root of 81672851 is about 433.8696172295.

The spelling of 81672851 in words is "eighty-one million, six hundred seventy-two thousand, eight hundred fifty-one".