665407377451 has 4 divisors (see below), whose sum is σ = 671512032400. Its totient is φ = 659302722504.

The previous prime is 665407377431. The next prime is 665407377473. The reversal of 665407377451 is 154773704566.

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

It is a cyclic number.

It is not a de Polignac number, because 665407377451 - 2⁵ = 665407377419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665407377392 and 665407377401.

It is not an unprimeable number, because it can be changed into a prime (665407377431) 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, 3052327311 + ... + 3052327528.

It is an arithmetic number, because the mean of its divisors is an integer number (167878008100).

Almost surely, 2^665407377451 is an apocalyptic number.

665407377451 is a deficient number, since it is larger than the sum of its proper divisors (6104654949).

665407377451 is a wasteful number, since it uses less digits than its factorization.

665407377451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6104654948.

The product of its (nonzero) digits is 14817600, while the sum is 55.

The spelling of 665407377451 in words is "six hundred sixty-five billion, four hundred seven million, three hundred seventy-seven thousand, four hundred fifty-one".