81634829 has 2 divisors, whose sum is σ = 81634830. Its totient is φ = 81634828.

The previous prime is 81634807. The next prime is 81634831. The reversal of 81634829 is 92843618.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76912900 + 4721929 = 8770^2 + 2173^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81634829 is a prime.

Together with 81634831, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81634859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40817414 + 40817415.

It is an arithmetic number, because the mean of its divisors is an integer number (40817415).

Almost surely, 2^81634829 is an apocalyptic number.

It is an amenable number.

81634829 is a deficient number, since it is larger than the sum of its proper divisors (1).

81634829 is an equidigital number, since it uses as much as digits as its factorization.

81634829 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 41.

The square root of 81634829 is about 9035.1994443952. The cubic root of 81634829 is about 433.8022788546.

The spelling of 81634829 in words is "eighty-one million, six hundred thirty-four thousand, eight hundred twenty-nine".