2991651840 has 704 divisors, whose sum is σ = 12026534400. Its totient is φ = 700710912.

The previous prime is 2991651827. The next prime is 2991651851. The reversal of 2991651840 is 481561992.

2991651840 is a `hidden beast` number, since 2 + 9 + 91 + 6 + 518 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 44651487 + ... + 44651553.

Almost surely, 2^2991651840 is an apocalyptic number.

2991651840 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 2991651840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6013267200).

2991651840 is an abundant number, since it is smaller than the sum of its proper divisors (9034882560).

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

2991651840 is a wasteful number, since it uses less digits than its factorization.

2991651840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The square root of 2991651840 is about 54695.9947345324. The cubic root of 2991651840 is about 1440.9105352436.

The spelling of 2991651840 in words is "two billion, nine hundred ninety-one million, six hundred fifty-one thousand, eight hundred forty".