2154013021 has 4 divisors (see below), whose sum is σ = 2223497344. Its totient is φ = 2084528700.

The previous prime is 2154013013. The next prime is 2154013031. The reversal of 2154013021 is 1203104512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2154013021 - 2³ = 2154013013 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2154013021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2154013031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34742115 + ... + 34742176.

It is an arithmetic number, because the mean of its divisors is an integer number (555874336).

Almost surely, 2^2154013021 is an apocalyptic number.

It is an amenable number.

2154013021 is a deficient number, since it is larger than the sum of its proper divisors (69484323).

2154013021 is an equidigital number, since it uses as much as digits as its factorization.

2154013021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69484322.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 2154013021 is about 46411.3458219001. The cubic root of 2154013021 is about 1291.4653982026.

Adding to 2154013021 its reverse (1203104512), we get a palindrome (3357117533).

The spelling of 2154013021 in words is "two billion, one hundred fifty-four million, thirteen thousand, twenty-one".