64906281440 has 384 divisors, whose sum is σ = 207114485760. Its totient is φ = 18562867200.

The previous prime is 64906281431. The next prime is 64906281443. The reversal of 64906281440 is 4418260946.

64906281440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 64906281391 and 64906281400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64906281443) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 28987841 + ... + 28990079.

It is an arithmetic number, because the mean of its divisors is an integer number (539360640).

Almost surely, 2^64906281440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64906281440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103557242880).

64906281440 is an abundant number, since it is smaller than the sum of its proper divisors (142208204320).

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

64906281440 is a wasteful number, since it uses less digits than its factorization.

64906281440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2466 (or 2458 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 44.

The spelling of 64906281440 in words is "sixty-four billion, nine hundred six million, two hundred eighty-one thousand, four hundred forty".