81924119 has 2 divisors, whose sum is σ = 81924120. Its totient is φ = 81924118.

The previous prime is 81924107. The next prime is 81924127. The reversal of 81924119 is 91142918.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81924119 - 2¹² = 81920023 is a prime.

It is a super-2 number, since 2×81924119² = 13423122547852322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81924169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40962059 + 40962060.

It is an arithmetic number, because the mean of its divisors is an integer number (40962060).

Almost surely, 2^81924119 is an apocalyptic number.

81924119 is a deficient number, since it is larger than the sum of its proper divisors (1).

81924119 is an equidigital number, since it uses as much as digits as its factorization.

81924119 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 35.

The square root of 81924119 is about 9051.1943410801. The cubic root of 81924119 is about 434.3140976257.

The spelling of 81924119 in words is "eighty-one million, nine hundred twenty-four thousand, one hundred nineteen".