646145460 has 72 divisors (see below), whose sum is σ = 1978016040. Its totient is φ = 170719488.

The previous prime is 646145453. The next prime is 646145473. The reversal of 646145460 is 64541646.

646145460 is a `hidden beast` number, since 646 + 1 + 4 + 5 + 4 + 6 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 13220496 + 632924964 = 3636^2 + 25158^2 .

It is a super-2 number, since 2×646145460² = 835007910957223200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3154 + ... + 36086.

It is an arithmetic number, because the mean of its divisors is an integer number (27472445).

Almost surely, 2^646145460 is an apocalyptic number.

646145460 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646145460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (989008020).

646145460 is an abundant number, since it is smaller than the sum of its proper divisors (1331870580).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646145460 is a wasteful number, since it uses less digits than its factorization.

646145460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33057 (or 33052 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 646145460 is about 25419.3914167904. The cubic root of 646145460 is about 864.5234257628.

The spelling of 646145460 in words is "six hundred forty-six million, one hundred forty-five thousand, four hundred sixty".