818378641 has 4 divisors (see below), whose sum is σ = 844777984. Its totient is φ = 791979300.

The previous prime is 818378597. The next prime is 818378647. The reversal of 818378641 is 146873818.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 818378641 - 2¹⁵ = 818345873 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 818378591 and 818378600.

It is not an unprimeable number, because it can be changed into a prime (818378647) 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, 13199625 + ... + 13199686.

It is an arithmetic number, because the mean of its divisors is an integer number (211194496).

Almost surely, 2^818378641 is an apocalyptic number.

It is an amenable number.

818378641 is a deficient number, since it is larger than the sum of its proper divisors (26399343).

818378641 is a wasteful number, since it uses less digits than its factorization.

818378641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26399342.

The product of its digits is 258048, while the sum is 46.

The square root of 818378641 is about 28607.3179623676. The cubic root of 818378641 is about 935.3728544314.

The spelling of 818378641 in words is "eight hundred eighteen million, three hundred seventy-eight thousand, six hundred forty-one".