81890995 has 8 divisors (see below), whose sum is σ = 101439360. Its totient is φ = 63399360.

The previous prime is 81890993. The next prime is 81891001. The reversal of 81890995 is 59909818.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81890995 - 2¹ = 81890993 is a prime.

It is a super-2 number, since 2×81890995² = 13412270124180050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81890993) 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, 264010 + ... + 264319.

It is an arithmetic number, because the mean of its divisors is an integer number (12679920).

Almost surely, 2^81890995 is an apocalyptic number.

81890995 is a deficient number, since it is larger than the sum of its proper divisors (19548365).

81890995 is a wasteful number, since it uses less digits than its factorization.

81890995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528365.

The product of its (nonzero) digits is 233280, while the sum is 49.

The square root of 81890995 is about 9049.3643423171. The cubic root of 81890995 is about 434.2555549984.

The spelling of 81890995 in words is "eighty-one million, eight hundred ninety thousand, nine hundred ninety-five".