81546213 has 32 divisors (see below), whose sum is σ = 129064960. Its totient is φ = 44815680.

The previous prime is 81546193. The next prime is 81546239. The reversal of 81546213 is 31264518.

It is not a de Polignac number, because 81546213 - 2⁵ = 81546181 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 (81546013) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 148806 + ... + 149352.

It is an arithmetic number, because the mean of its divisors is an integer number (4033280).

Almost surely, 2^81546213 is an apocalyptic number.

It is an amenable number.

81546213 is a deficient number, since it is larger than the sum of its proper divisors (47518747).

81546213 is a wasteful number, since it uses less digits than its factorization.

81546213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 817.

The product of its digits is 5760, while the sum is 30.

The square root of 81546213 is about 9030.2941812546. The cubic root of 81546213 is about 433.6452554314.

The spelling of 81546213 in words is "eighty-one million, five hundred forty-six thousand, two hundred thirteen".