646228799 has 4 divisors (see below), whose sum is σ = 650345064. Its totient is φ = 642112536.

The previous prime is 646228771. The next prime is 646228831. The reversal of 646228799 is 997822646.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 997822646 = 2 ⋅498911323.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646228799 is a prime.

It is a super-2 number, since 2×646228799² = 835223321313964802, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 646228799.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646278799) 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, 2057897 + ... + 2058210.

It is an arithmetic number, because the mean of its divisors is an integer number (162586266).

Almost surely, 2^646228799 is an apocalyptic number.

646228799 is a deficient number, since it is larger than the sum of its proper divisors (4116265).

646228799 is a wasteful number, since it uses less digits than its factorization.

646228799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4116264.

The product of its digits is 2612736, while the sum is 53.

The square root of 646228799 is about 25421.0306439373. The cubic root of 646228799 is about 864.5605925335.

The spelling of 646228799 in words is "six hundred forty-six million, two hundred twenty-eight thousand, seven hundred ninety-nine".