65121421 has 4 divisors (see below), whose sum is σ = 67222144. Its totient is φ = 63020700.

The previous prime is 65121401. The next prime is 65121431. The reversal of 65121421 is 12412156.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 65121421 - 2⁷ = 65121293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 65121392 and 65121401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65121401) 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, 1050315 + ... + 1050376.

It is an arithmetic number, because the mean of its divisors is an integer number (16805536).

Almost surely, 2^65121421 is an apocalyptic number.

It is an amenable number.

65121421 is a deficient number, since it is larger than the sum of its proper divisors (2100723).

65121421 is a wasteful number, since it uses less digits than its factorization.

65121421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2100722.

The product of its digits is 480, while the sum is 22.

The square root of 65121421 is about 8069.7844456962. The cubic root of 65121421 is about 402.3227793813.

Adding to 65121421 its reverse (12412156), we get a palindrome (77533577).

The spelling of 65121421 in words is "sixty-five million, one hundred twenty-one thousand, four hundred twenty-one".