81429519 has 4 divisors (see below), whose sum is σ = 108572696. Its totient is φ = 54286344.

The previous prime is 81429511. The next prime is 81429527. The reversal of 81429519 is 91592418.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (81429511) and next prime (81429527).

It is not a de Polignac number, because 81429519 - 2³ = 81429511 is a prime.

It is a super-2 number, since 2×81429519² = 13261533129142722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81429511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13571584 + ... + 13571589.

It is an arithmetic number, because the mean of its divisors is an integer number (27143174).

Almost surely, 2^81429519 is an apocalyptic number.

81429519 is a deficient number, since it is larger than the sum of its proper divisors (27143177).

81429519 is a wasteful number, since it uses less digits than its factorization.

81429519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27143176.

The product of its digits is 25920, while the sum is 39.

The square root of 81429519 is about 9023.8306167614. The cubic root of 81429519 is about 433.4383054699.

The spelling of 81429519 in words is "eighty-one million, four hundred twenty-nine thousand, five hundred nineteen".