81633065 has 8 divisors (see below), whose sum is σ = 103722120. Its totient is φ = 61464832.

The previous prime is 81633037. The next prime is 81633119. The reversal of 81633065 is 56033618.

It can be written as a sum of positive squares in 4 ways, for example, as 2920681 + 78712384 = 1709^2 + 8872^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81633065 - 2⁸ = 81632809 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 480110 + ... + 480279.

It is an arithmetic number, because the mean of its divisors is an integer number (12965265).

Almost surely, 2^81633065 is an apocalyptic number.

81633065 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

81633065 is a deficient number, since it is larger than the sum of its proper divisors (22089055).

81633065 is a wasteful number, since it uses less digits than its factorization.

81633065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 960411.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 81633065 is about 9035.1018256575. The cubic root of 81633065 is about 433.7991542375.

The spelling of 81633065 in words is "eighty-one million, six hundred thirty-three thousand, sixty-five".