65211391 has 4 divisors (see below), whose sum is σ = 74527312. Its totient is φ = 55895472.

The previous prime is 65211323. The next prime is 65211403. The reversal of 65211391 is 19311256.

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

It is a cyclic number.

It is not a de Polignac number, because 65211391 - 2¹⁵ = 65178623 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 (65211491) 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, 4657950 + ... + 4657963.

It is an arithmetic number, because the mean of its divisors is an integer number (18631828).

Almost surely, 2^65211391 is an apocalyptic number.

65211391 is a deficient number, since it is larger than the sum of its proper divisors (9315921).

65211391 is an equidigital number, since it uses as much as digits as its factorization.

65211391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9315920.

The product of its digits is 1620, while the sum is 28.

The square root of 65211391 is about 8075.3570199713. The cubic root of 65211391 is about 402.5079735570.

The spelling of 65211391 in words is "sixty-five million, two hundred eleven thousand, three hundred ninety-one".