646457245 has 20 divisors (see below), whose sum is σ = 905003100. Its totient is φ = 443276736.

The previous prime is 646457213. The next prime is 646457257. The reversal of 646457245 is 542754646.

It can be written as a sum of positive squares in 2 ways, for example, as 505845081 + 140612164 = 22491^2 + 11858^2 .

It is not a de Polignac number, because 646457245 - 2⁵ = 646457213 is a prime.

It is a super-2 number, since 2×646457245² = 835813939225980050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 14920 + ... + 38929.

It is an arithmetic number, because the mean of its divisors is an integer number (45250155).

Almost surely, 2^646457245 is an apocalyptic number.

It is an amenable number.

646457245 is a deficient number, since it is larger than the sum of its proper divisors (258545855).

646457245 is an frugal number, since it uses more digits than its factorization.

646457245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53882 (or 53861 counting only the distinct ones).

The product of its digits is 806400, while the sum is 43.

The square root of 646457245 is about 25425.5234951023. The cubic root of 646457245 is about 864.6624564248.

The spelling of 646457245 in words is "six hundred forty-six million, four hundred fifty-seven thousand, two hundred forty-five".