2154621013 has 4 divisors (see below), whose sum is σ = 2156253388. Its totient is φ = 2152988640.

The previous prime is 2154621011. The next prime is 2154621019. The reversal of 2154621013 is 3101264512.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2105157924 + 49463089 = 45882^2 + 7033^2 .

It is a cyclic number.

It is not a de Polignac number, because 2154621013 - 2¹ = 2154621011 is a prime.

It is a super-2 number, since 2×2154621013² = 9284783419322292338, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2154621011) 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, 814206 + ... + 816847.

It is an arithmetic number, because the mean of its divisors is an integer number (539063347).

Almost surely, 2^2154621013 is an apocalyptic number.

It is an amenable number.

2154621013 is a deficient number, since it is larger than the sum of its proper divisors (1632375).

2154621013 is a wasteful number, since it uses less digits than its factorization.

2154621013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1632374.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 2154621013 is about 46417.8953960647. The cubic root of 2154621013 is about 1291.5868965032.

Adding to 2154621013 its reverse (3101264512), we get a palindrome (5255885525).

The spelling of 2154621013 in words is "two billion, one hundred fifty-four million, six hundred twenty-one thousand, thirteen".