81963100 has 36 divisors (see below), whose sum is σ = 182207088. Its totient is φ = 31984000.

The previous prime is 81963097. The next prime is 81963113. The reversal of 81963100 is 136918.

It is a happy number.

It is a super-2 number, since 2×81963100² = 13435899523220000, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5896 + ... + 14095.

It is an arithmetic number, because the mean of its divisors is an integer number (5061308).

Almost surely, 2^81963100 is an apocalyptic number.

It is an amenable number.

81963100 is an abundant number, since it is smaller than the sum of its proper divisors (100243988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81963100 is a wasteful number, since it uses less digits than its factorization.

81963100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20046 (or 20039 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 81963100 is about 9053.3474472153. The cubic root of 81963100 is about 434.3829715770.

The spelling of 81963100 in words is "eighty-one million, nine hundred sixty-three thousand, one hundred".