21057013004377 has 12 divisors (see below), whose sum is σ = 24533106276276. Its totient is φ = 18020710901760.

The previous prime is 21057013004369. The next prime is 21057013004399. The reversal of 21057013004377 is 77340031075012.

It can be written as a sum of positive squares in 2 ways, for example, as 20497133445376 + 559879559001 = 4527376^2 + 748251^2 .

It is not a de Polignac number, because 21057013004377 - 2³ = 21057013004369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21057013004177) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 335175268 + ... + 335238085.

It is an arithmetic number, because the mean of its divisors is an integer number (2044425523023).

Almost surely, 2^{21057013004377} is an apocalyptic number.

It is an amenable number.

21057013004377 is a deficient number, since it is larger than the sum of its proper divisors (3476093271899).

21057013004377 is an equidigital number, since it uses as much as digits as its factorization.

21057013004377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670414008 (or 670414001 counting only the distinct ones).

The product of its (nonzero) digits is 123480, while the sum is 40.

Adding to 21057013004377 its reverse (77340031075012), we get a palindrome (98397044079389).

The spelling of 21057013004377 in words is "twenty-one trillion, fifty-seven billion, thirteen million, four thousand, three hundred seventy-seven".