66961379 has 4 divisors (see below), whose sum is σ = 68771184. Its totient is φ = 65151576.

The previous prime is 66961373. The next prime is 66961381. The reversal of 66961379 is 97316966.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66961379 is a prime.

It is a pancake number, because a pancake can be divided into 66961379 parts by 11572 straight cuts.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66961373) 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, 904847 + ... + 904920.

It is an arithmetic number, because the mean of its divisors is an integer number (17192796).

Almost surely, 2^66961379 is an apocalyptic number.

66961379 is a deficient number, since it is larger than the sum of its proper divisors (1809805).

66961379 is a wasteful number, since it uses less digits than its factorization.

66961379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1809804.

The product of its digits is 367416, while the sum is 47.

The square root of 66961379 is about 8182.9932787459. The cubic root of 66961379 is about 406.0767547218.

The spelling of 66961379 in words is "sixty-six million, nine hundred sixty-one thousand, three hundred seventy-nine".