65212421 has 4 divisors (see below), whose sum is σ = 65884812. Its totient is φ = 64540032.

The previous prime is 65212397. The next prime is 65212439. The reversal of 65212421 is 12421256.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 21520321 + 43692100 = 4639^2 + 6610^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65212421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65212471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 336050 + ... + 336243.

It is an arithmetic number, because the mean of its divisors is an integer number (16471203).

Almost surely, 2^65212421 is an apocalyptic number.

It is an amenable number.

65212421 is a deficient number, since it is larger than the sum of its proper divisors (672391).

65212421 is an equidigital number, since it uses as much as digits as its factorization.

65212421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 672390.

The product of its digits is 960, while the sum is 23.

The square root of 65212421 is about 8075.4207939896. The cubic root of 65212421 is about 402.5100927217.

Adding to 65212421 its reverse (12421256), we get a palindrome (77633677).

The spelling of 65212421 in words is "sixty-five million, two hundred twelve thousand, four hundred twenty-one".