81120429 has 12 divisors (see below), whose sum is σ = 126187516. Its totient is φ = 49920192.

The previous prime is 81120407. The next prime is 81120433. The reversal of 81120429 is 92402118.

It can be written as a sum of positive squares in 2 ways, for example, as 22184100 + 58936329 = 4710^2 + 7677^2 .

It is not a de Polignac number, because 81120429 - 2⁹ = 81119917 is a prime.

It is a super-2 number, since 2×81120429² = 13161048002288082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81120469) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 346552 + ... + 346785.

Almost surely, 2^81120429 is an apocalyptic number.

It is an amenable number.

81120429 is a deficient number, since it is larger than the sum of its proper divisors (45067087).

81120429 is a wasteful number, since it uses less digits than its factorization.

81120429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693356 (or 693353 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 81120429 is about 9006.6880150253. The cubic root of 81120429 is about 432.8891953709.

The spelling of 81120429 in words is "eighty-one million, one hundred twenty thousand, four hundred twenty-nine".