2780144640 has 1056 divisors, whose sum is σ = 12946210560. Its totient is φ = 552075264.

The previous prime is 2780144639. The next prime is 2780144641. The reversal of 2780144640 is 464410872.

2780144640 is a `hidden beast` number, since 2 + 7 + 8 + 0 + 1 + 4 + 4 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (2780144639) and next prime (2780144641).

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

It is a junction number, because it is equal to n+sod(n) for n = 2780144595 and 2780144604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2780144641) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 163537912 + ... + 163537928.

Almost surely, 2^2780144640 is an apocalyptic number.

2780144640 is a gapful number since it is divisible by the number (20) 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 2780144640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6473105280).

2780144640 is an abundant number, since it is smaller than the sum of its proper divisors (10166065920).

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

2780144640 is a wasteful number, since it uses less digits than its factorization.

2780144640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The square root of 2780144640 is about 52727.0769149969. The cubic root of 2780144640 is about 1406.1202532738.

The spelling of 2780144640 in words is "two billion, seven hundred eighty million, one hundred forty-four thousand, six hundred forty".