21169038739 has 2 divisors, whose sum is σ = 21169038740. Its totient is φ = 21169038738.

The previous prime is 21169038661. The next prime is 21169038749. The reversal of 21169038739 is 93783096112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21169038739 - 2⁹ = 21169038227 is a prime.

It is a super-2 number, since 2×21169038739² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21169038692 and 21169038701.

It is not a weakly prime, because it can be changed into another prime (21169038749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10584519369 + 10584519370.

It is an arithmetic number, because the mean of its divisors is an integer number (10584519370).

Almost surely, 2^21169038739 is an apocalyptic number.

21169038739 is a deficient number, since it is larger than the sum of its proper divisors (1).

21169038739 is an equidigital number, since it uses as much as digits as its factorization.

21169038739 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 489888, while the sum is 49.

The spelling of 21169038739 in words is "twenty-one billion, one hundred sixty-nine million, thirty-eight thousand, seven hundred thirty-nine".