65431021 has 8 divisors (see below), whose sum is σ = 68477760. Its totient is φ = 62401152.

The previous prime is 65430997. The next prime is 65431031. The reversal of 65431021 is 12013456.

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 65431021 - 2¹⁵ = 65398253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 65430983 and 65431001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65431031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4090 + ... + 12148.

It is an arithmetic number, because the mean of its divisors is an integer number (8559720).

Almost surely, 2^65431021 is an apocalyptic number.

It is an amenable number.

65431021 is a deficient number, since it is larger than the sum of its proper divisors (3046739).

65431021 is a wasteful number, since it uses less digits than its factorization.

65431021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8435.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 65431021 is about 8088.9443687047. The cubic root of 65431021 is about 402.9593454424.

Adding to 65431021 its reverse (12013456), we get a palindrome (77444477).

The spelling of 65431021 in words is "sixty-five million, four hundred thirty-one thousand, twenty-one".