81612965 has 16 divisors (see below), whose sum is σ = 112085760. Its totient is φ = 55883520.

The previous prime is 81612941. The next prime is 81612983. The reversal of 81612965 is 56921618.

It is not a de Polignac number, because 81612965 - 2¹⁰ = 81611941 is a prime.

It is a super-3 number, since 3×81612965³ (a number of 25 digits) contains 333 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34160 + ... + 36470.

It is an arithmetic number, because the mean of its divisors is an integer number (7005360).

Almost surely, 2^81612965 is an apocalyptic number.

It is an amenable number.

81612965 is a deficient number, since it is larger than the sum of its proper divisors (30472795).

81612965 is a wasteful number, since it uses less digits than its factorization.

81612965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3332.

The product of its digits is 25920, while the sum is 38.

The square root of 81612965 is about 9033.9894288183. The cubic root of 81612965 is about 433.7635474290.

The spelling of 81612965 in words is "eighty-one million, six hundred twelve thousand, nine hundred sixty-five".