1945297640 has 192 divisors, whose sum is σ = 5308934400. Its totient is φ = 636894720.

The previous prime is 1945297639. The next prime is 1945297693. The reversal of 1945297640 is 467925491.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2705201 + ... + 2705919.

It is an arithmetic number, because the mean of its divisors is an integer number (27650700).

Almost surely, 2^1945297640 is an apocalyptic number.

1945297640 is a gapful number since it is divisible by the number (10) 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 1945297640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2654467200).

1945297640 is an abundant number, since it is smaller than the sum of its proper divisors (3363636760).

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

1945297640 is a wasteful number, since it uses less digits than its factorization.

1945297640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808 (or 793 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 47.

The square root of 1945297640 is about 44105.5284516578. The cubic root of 1945297640 is about 1248.3279275362.

The spelling of 1945297640 in words is "one billion, nine hundred forty-five million, two hundred ninety-seven thousand, six hundred forty".