64687540 has 12 divisors (see below), whose sum is σ = 135843876. Its totient is φ = 25875008.

The previous prime is 64687531. The next prime is 64687543. The reversal of 64687540 is 4578646.

It can be written as a sum of positive squares in 2 ways, for example, as 46076944 + 18610596 = 6788^2 + 4314^2 .

It is a junction number, because it is equal to n+sod(n) for n = 64687493 and 64687502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64687543) 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, 1617169 + ... + 1617208.

It is an arithmetic number, because the mean of its divisors is an integer number (11320323).

Almost surely, 2^64687540 is an apocalyptic number.

It is an amenable number.

64687540 is an abundant number, since it is smaller than the sum of its proper divisors (71156336).

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

64687540 is a wasteful number, since it uses less digits than its factorization.

64687540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3234386 (or 3234384 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 40.

The square root of 64687540 is about 8042.8564577518. The cubic root of 64687540 is about 401.4272761496.

The spelling of 64687540 in words is "sixty-four million, six hundred eighty-seven thousand, five hundred forty".