66361799 has 4 divisors (see below), whose sum is σ = 75842064. Its totient is φ = 56881536.

The previous prime is 66361787. The next prime is 66361811. The reversal of 66361799 is 99716366.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (66361787) and next prime (66361811).

It is a cyclic number.

It is not a de Polignac number, because 66361799 - 2¹² = 66357703 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 (66361709) 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, 4740122 + ... + 4740135.

It is an arithmetic number, because the mean of its divisors is an integer number (18960516).

Almost surely, 2^66361799 is an apocalyptic number.

66361799 is a deficient number, since it is larger than the sum of its proper divisors (9480265).

66361799 is an equidigital number, since it uses as much as digits as its factorization.

66361799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9480264.

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

The square root of 66361799 is about 8146.2751610782. The cubic root of 66361799 is about 404.8610995504.

The spelling of 66361799 in words is "sixty-six million, three hundred sixty-one thousand, seven hundred ninety-nine".