81929963 has 2 divisors, whose sum is σ = 81929964. Its totient is φ = 81929962.

The previous prime is 81929927. The next prime is 81929989. The reversal of 81929963 is 36992918.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81929963 - 2⁶ = 81929899 is a prime.

It is not a weakly prime, because it can be changed into another prime (81929363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40964981 + 40964982.

It is an arithmetic number, because the mean of its divisors is an integer number (40964982).

Almost surely, 2^81929963 is an apocalyptic number.

81929963 is a deficient number, since it is larger than the sum of its proper divisors (1).

81929963 is an equidigital number, since it uses as much as digits as its factorization.

81929963 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 47.

The square root of 81929963 is about 9051.5171656469. The cubic root of 81929963 is about 434.3244245448.

The spelling of 81929963 in words is "eighty-one million, nine hundred twenty-nine thousand, nine hundred sixty-three".