81235996 has 48 divisors (see below), whose sum is σ = 157489920. Its totient is φ = 36495360.

The previous prime is 81235993. The next prime is 81236003. The reversal of 81235996 is 69953218.

It is a happy number.

It is a super-2 number, since 2×81235996² = 13198574092224032, which contains 22 as substring.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81235991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 187396 + ... + 187828.

It is an arithmetic number, because the mean of its divisors is an integer number (3281040).

Almost surely, 2^81235996 is an apocalyptic number.

It is an amenable number.

81235996 is a deficient number, since it is larger than the sum of its proper divisors (76253924).

81235996 is a wasteful number, since it uses less digits than its factorization.

81235996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 574 (or 572 counting only the distinct ones).

The product of its digits is 116640, while the sum is 43.

The square root of 81235996 is about 9013.1013530305. The cubic root of 81235996 is about 433.0946675229.

The spelling of 81235996 in words is "eighty-one million, two hundred thirty-five thousand, nine hundred ninety-six".