2564668240 has 20 divisors (see below), whose sum is σ = 5962853844. Its totient is φ = 1025867264.

The previous prime is 2564668237. The next prime is 2564668247. The reversal of 2564668240 is 428664652.

It can be written as a sum of positive squares in 2 ways, for example, as 1894686784 + 669981456 = 43528^2 + 25884^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2564668247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16029097 + ... + 16029256.

Almost surely, 2^2564668240 is an apocalyptic number.

2564668240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2564668240 is an abundant number, since it is smaller than the sum of its proper divisors (3398185604).

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

2564668240 is a wasteful number, since it uses less digits than its factorization.

2564668240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32058366 (or 32058360 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 43.

The square root of 2564668240 is about 50642.5536480932. The cubic root of 2564668240 is about 1368.8117709729.

The spelling of 2564668240 in words is "two billion, five hundred sixty-four million, six hundred sixty-eight thousand, two hundred forty".