2120631851 has 4 divisors (see below), whose sum is σ = 2283757392. Its totient is φ = 1957506312.

The previous prime is 2120631847. The next prime is 2120631859. The reversal of 2120631851 is 1581360212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2120631851 - 2² = 2120631847 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2120631859) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 81562751 + ... + 81562776.

It is an arithmetic number, because the mean of its divisors is an integer number (570939348).

Almost surely, 2^2120631851 is an apocalyptic number.

2120631851 is a deficient number, since it is larger than the sum of its proper divisors (163125541).

2120631851 is a wasteful number, since it uses less digits than its factorization.

2120631851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163125540.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 2120631851 is about 46050.3186851079. The cubic root of 2120631851 is about 1284.7592701607.

The spelling of 2120631851 in words is "two billion, one hundred twenty million, six hundred thirty-one thousand, eight hundred fifty-one".