65407021 has 2 divisors, whose sum is σ = 65407022. Its totient is φ = 65407020.

The previous prime is 65407019. The next prime is 65407031. The reversal of 65407021 is 12070456.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57078025 + 8328996 = 7555^2 + 2886^2 .

It is a cyclic number.

It is not a de Polignac number, because 65407021 - 2¹ = 65407019 is a prime.

Together with 65407019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65407031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32703510 + 32703511.

It is an arithmetic number, because the mean of its divisors is an integer number (32703511).

Almost surely, 2^65407021 is an apocalyptic number.

It is an amenable number.

65407021 is a deficient number, since it is larger than the sum of its proper divisors (1).

65407021 is an equidigital number, since it uses as much as digits as its factorization.

65407021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 65407021 is about 8087.4607263343. The cubic root of 65407021 is about 402.9100711235.

Adding to 65407021 its reverse (12070456), we get a palindrome (77477477).

The spelling of 65407021 in words is "sixty-five million, four hundred seven thousand, twenty-one".