81210151 has 8 divisors (see below), whose sum is σ = 90265104. Its totient is φ = 72433920.

The previous prime is 81210089. The next prime is 81210169. The reversal of 81210151 is 15101218.

It is a happy number.

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 81210151 - 2¹³ = 81201959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81210191) 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, 69066 + ... + 70231.

It is an arithmetic number, because the mean of its divisors is an integer number (11283138).

Almost surely, 2^81210151 is an apocalyptic number.

81210151 is a deficient number, since it is larger than the sum of its proper divisors (9054953).

81210151 is a wasteful number, since it uses less digits than its factorization.

81210151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139361.

The product of its (nonzero) digits is 80, while the sum is 19.

The square root of 81210151 is about 9011.6674927563. The cubic root of 81210151 is about 433.0487333743.

Adding to 81210151 its reverse (15101218), we get a palindrome (96311369).

The spelling of 81210151 in words is "eighty-one million, two hundred ten thousand, one hundred fifty-one".