81950236 has 18 divisors (see below), whose sum is σ = 148195320. Its totient is φ = 39651480.

The previous prime is 81950213. The next prime is 81950237. The reversal of 81950236 is 63205918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81950237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6816 + ... + 14503.

Almost surely, 2^81950236 is an apocalyptic number.

It is an amenable number.

81950236 is a deficient number, since it is larger than the sum of its proper divisors (66245084).

81950236 is a wasteful number, since it uses less digits than its factorization.

81950236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21385 (or 21352 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 81950236 is about 9052.6369638907. The cubic root of 81950236 is about 434.3602451107.

The spelling of 81950236 in words is "eighty-one million, nine hundred fifty thousand, two hundred thirty-six".