81652199 has 4 divisors (see below), whose sum is σ = 81994080. Its totient is φ = 81310320.

The previous prime is 81652189. The next prime is 81652217. The reversal of 81652199 is 99125618.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81652199 - 2⁴ = 81652183 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 (81652159) 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, 170582 + ... + 171059.

It is an arithmetic number, because the mean of its divisors is an integer number (20498520).

Almost surely, 2^81652199 is an apocalyptic number.

81652199 is a deficient number, since it is larger than the sum of its proper divisors (341881).

81652199 is a wasteful number, since it uses less digits than its factorization.

81652199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341880.

The product of its digits is 38880, while the sum is 41.

The square root of 81652199 is about 9036.1606338090. The cubic root of 81652199 is about 433.8330443636.

The spelling of 81652199 in words is "eighty-one million, six hundred fifty-two thousand, one hundred ninety-nine".