1947320640 has 252 divisors, whose sum is σ = 7072824564. Its totient is φ = 491692032.

The previous prime is 1947320597. The next prime is 1947320653. The reversal of 1947320640 is 460237491.

1947320640 is a `hidden beast` number, since 1 + 9 + 4 + 7 + 3 + 2 + 0 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 300259584 + 1647061056 = 17328^2 + 40584^2 .

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 = 1947320595 and 1947320604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1038744 + ... + 1040616.

Almost surely, 2^1947320640 is an apocalyptic number.

1947320640 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 1947320640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3536412282).

1947320640 is an abundant number, since it is smaller than the sum of its proper divisors (5125503924).

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

1947320640 is a wasteful number, since it uses less digits than its factorization.

1947320640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1934 (or 1902 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 1947320640 is about 44128.4561252714. The cubic root of 1947320640 is about 1248.7605078670.

The spelling of 1947320640 in words is "one billion, nine hundred forty-seven million, three hundred twenty thousand, six hundred forty".