2120154021 has 10 divisors (see below), whose sum is σ = 3167143782. Its totient is φ = 1413435960.

The previous prime is 2120154019. The next prime is 2120154037. The reversal of 2120154021 is 1204510212.

2120154021 is a `hidden beast` number, since 2 + 120 + 1 + 540 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2016908100 + 103245921 = 44910^2 + 10161^2 .

It is not a de Polignac number, because 2120154021 - 2¹ = 2120154019 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2120153985 and 2120154003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120154041) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 13087290 + ... + 13087451.

Almost surely, 2^2120154021 is an apocalyptic number.

It is an amenable number.

2120154021 is a deficient number, since it is larger than the sum of its proper divisors (1046989761).

2120154021 is an equidigital number, since it uses as much as digits as its factorization.

2120154021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26174753 (or 26174744 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 2120154021 is about 46045.1302636880. The cubic root of 2120154021 is about 1284.6627670617.

Adding to 2120154021 its reverse (1204510212), we get a palindrome (3324664233).

The spelling of 2120154021 in words is "two billion, one hundred twenty million, one hundred fifty-four thousand, twenty-one".