65520391 has 8 divisors (see below), whose sum is σ = 67731968. Its totient is φ = 63315000.

The previous prime is 65520373. The next prime is 65520407. The reversal of 65520391 is 19302556.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 65520391 - 2⁵ = 65520359 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65520331) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31576 + ... + 33586.

It is an arithmetic number, because the mean of its divisors is an integer number (8466496).

Almost surely, 2^65520391 is an apocalyptic number.

65520391 is a deficient number, since it is larger than the sum of its proper divisors (2211577).

65520391 is a wasteful number, since it uses less digits than its factorization.

65520391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3093.

The product of its (nonzero) digits is 8100, while the sum is 31.

The square root of 65520391 is about 8094.4666902768. The cubic root of 65520391 is about 403.1427247860.

The spelling of 65520391 in words is "sixty-five million, five hundred twenty thousand, three hundred ninety-one".