81625535 has 4 divisors (see below), whose sum is σ = 97950648. Its totient is φ = 65300424.

The previous prime is 81625519. The next prime is 81625541. The reversal of 81625535 is 53552618.

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

It is a cyclic number.

It is not a de Polignac number, because 81625535 - 2⁴ = 81625519 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81625495 and 81625504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8162549 + ... + 8162558.

It is an arithmetic number, because the mean of its divisors is an integer number (24487662).

Almost surely, 2^81625535 is an apocalyptic number.

81625535 is a deficient number, since it is larger than the sum of its proper divisors (16325113).

81625535 is a wasteful number, since it uses less digits than its factorization.

81625535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16325112.

The product of its digits is 36000, while the sum is 35.

The square root of 81625535 is about 9034.6851079603. The cubic root of 81625535 is about 433.7858156552.

The spelling of 81625535 in words is "eighty-one million, six hundred twenty-five thousand, five hundred thirty-five".