66763913 has 6 divisors (see below), whose sum is σ = 70922526. Its totient is φ = 62836352.

The previous prime is 66763909. The next prime is 66763919. The reversal of 66763913 is 31936766.

It can be written as a sum of positive squares in 3 ways, for example, as 33953929 + 32809984 = 5827^2 + 5728^2 .

It is not a de Polignac number, because 66763913 - 2² = 66763909 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66763919) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 115220 + ... + 115797.

It is an arithmetic number, because the mean of its divisors is an integer number (11820421).

Almost surely, 2^66763913 is an apocalyptic number.

It is an amenable number.

66763913 is a deficient number, since it is larger than the sum of its proper divisors (4158613).

66763913 is a wasteful number, since it uses less digits than its factorization.

66763913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231051 (or 231034 counting only the distinct ones).

The product of its digits is 122472, while the sum is 41.

The square root of 66763913 is about 8170.9187365926. The cubic root of 66763913 is about 405.6771945326.

It can be divided in two parts, 66763 and 913, that added together give a palindrome (67676).

The spelling of 66763913 in words is "sixty-six million, seven hundred sixty-three thousand, nine hundred thirteen".