65312121 has 8 divisors (see below), whose sum is σ = 99523264. Its totient is φ = 37321200.

The previous prime is 65312099. The next prime is 65312153. The reversal of 65312121 is 12121356.

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

It is not a de Polignac number, because 65312121 - 2¹⁵ = 65279353 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 3110101 = 65312121 / (6 + 5 + 3 + 1 + 2 + 1 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65312021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1555030 + ... + 1555071.

It is an arithmetic number, because the mean of its divisors is an integer number (12440408).

Almost surely, 2^65312121 is an apocalyptic number.

It is an amenable number.

65312121 is a deficient number, since it is larger than the sum of its proper divisors (34211143).

65312121 is a wasteful number, since it uses less digits than its factorization.

65312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3110111.

The product of its digits is 360, while the sum is 21.

The square root of 65312121 is about 8081.5914893046. The cubic root of 65312121 is about 402.7151141064.

Adding to 65312121 its reverse (12121356), we get a palindrome (77433477).

The spelling of 65312121 in words is "sixty-five million, three hundred twelve thousand, one hundred twenty-one".