81870367 has 4 divisors (see below), whose sum is σ = 81915336. Its totient is φ = 81825400.

The previous prime is 81870343. The next prime is 81870377. The reversal of 81870367 is 76307818.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81870367 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81870377) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19633 + ... + 23434.

It is an arithmetic number, because the mean of its divisors is an integer number (20478834).

Almost surely, 2^81870367 is an apocalyptic number.

81870367 is a deficient number, since it is larger than the sum of its proper divisors (44969).

81870367 is a wasteful number, since it uses less digits than its factorization.

81870367 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44968.

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 81870367 is about 9048.2245219711. The cubic root of 81870367 is about 434.2190895488.

The spelling of 81870367 in words is "eighty-one million, eight hundred seventy thousand, three hundred sixty-seven".