65706421 has 4 divisors (see below), whose sum is σ = 71679744. Its totient is φ = 59733100.

The previous prime is 65706401. The next prime is 65706437. The reversal of 65706421 is 12460756.

It is a happy number.

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 65706421 - 2²¹ = 63609269 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65706401) 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, 2986645 + ... + 2986666.

It is an arithmetic number, because the mean of its divisors is an integer number (17919936).

Almost surely, 2^65706421 is an apocalyptic number.

It is an amenable number.

65706421 is a deficient number, since it is larger than the sum of its proper divisors (5973323).

65706421 is a wasteful number, since it uses less digits than its factorization.

65706421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5973322.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 65706421 is about 8105.9497284402. The cubic root of 65706421 is about 403.5239077692.

The spelling of 65706421 in words is "sixty-five million, seven hundred six thousand, four hundred twenty-one".