66520347 has 16 divisors (see below), whose sum is σ = 93937920. Its totient is φ = 41782752.

The previous prime is 66520331. The next prime is 66520351. The reversal of 66520347 is 74302566.

It is not a de Polignac number, because 66520347 - 2⁴ = 66520331 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66520367) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2572 + ... + 11817.

It is an arithmetic number, because the mean of its divisors is an integer number (5871120).

Almost surely, 2^66520347 is an apocalyptic number.

66520347 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

66520347 is a deficient number, since it is larger than the sum of its proper divisors (27417573).

66520347 is a wasteful number, since it uses less digits than its factorization.

66520347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14482.

The product of its (nonzero) digits is 30240, while the sum is 33.

The square root of 66520347 is about 8156.0006743501. Note that the first 3 decimals coincide. The cubic root of 66520347 is about 405.1832671561.

It can be divided in two parts, 665 and 20347, that added together give a palindrome (21012).

The spelling of 66520347 in words is "sixty-six million, five hundred twenty thousand, three hundred forty-seven".