81672195 has 32 divisors (see below), whose sum is σ = 148760064. Its totient is φ = 37875200.

The previous prime is 81672193. The next prime is 81672257. The reversal of 81672195 is 59127618.

It is not a de Polignac number, because 81672195 - 2¹ = 81672193 is a prime.

It is a super-2 number, since 2×81672195² = 13340694872236050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81672193) 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, 6966 + ... + 14555.

It is an arithmetic number, because the mean of its divisors is an integer number (4648752).

Almost surely, 2^81672195 is an apocalyptic number.

81672195 is a deficient number, since it is larger than the sum of its proper divisors (67087869).

81672195 is a wasteful number, since it uses less digits than its factorization.

81672195 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21563.

The product of its digits is 30240, while the sum is 39.

The square root of 81672195 is about 9037.2670094448. The cubic root of 81672195 is about 433.8684556063.

It can be divided in two parts, 81 and 672195, that added together give a palindrome (672276).

The spelling of 81672195 in words is "eighty-one million, six hundred seventy-two thousand, one hundred ninety-five".