2051421660 has 96 divisors (see below), whose sum is σ = 6423117120. Its totient is φ = 543538944.

The previous prime is 2051421613. The next prime is 2051421703. The reversal of 2051421660 is 661241502.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72682 + ... + 96878.

It is an arithmetic number, because the mean of its divisors is an integer number (66907470).

Almost surely, 2^2051421660 is an apocalyptic number.

2051421660 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 2051421660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3211558560).

2051421660 is an abundant number, since it is smaller than the sum of its proper divisors (4371695460).

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

2051421660 is a wasteful number, since it uses less digits than its factorization.

2051421660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24372 (or 24364 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 2051421660 is about 45292.6225780756. The cubic root of 2051421660 is about 1270.6276807153.

The spelling of 2051421660 in words is "two billion, fifty-one million, four hundred twenty-one thousand, six hundred sixty".