2021551540 has 96 divisors (see below), whose sum is σ = 4483584000. Its totient is φ = 764674560.

The previous prime is 2021551513. The next prime is 2021551579. The reversal of 2021551540 is 451551202.

It is a super-3 number, since 3×2021551540³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7297882 + ... + 7298158.

It is an arithmetic number, because the mean of its divisors is an integer number (46704000).

Almost surely, 2^2021551540 is an apocalyptic number.

2021551540 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 2021551540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2241792000).

2021551540 is an abundant number, since it is smaller than the sum of its proper divisors (2462032460).

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

2021551540 is a wasteful number, since it uses less digits than its factorization.

2021551540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545 (or 543 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 2021551540 is about 44961.6674512857. The cubic root of 2021551540 is about 1264.4304309400.

The spelling of 2021551540 in words is "two billion, twenty-one million, five hundred fifty-one thousand, five hundred forty".