21291525917159 has 2 divisors, whose sum is σ = 21291525917160. Its totient is φ = 21291525917158.

The previous prime is 21291525917099. The next prime is 21291525917287. The reversal of 21291525917159 is 95171952519212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21291525917159 - 2⁴⁴ = 3699339872743 is a prime.

It is a super-2 number, since 2×21291525917159² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 21291525917098 and 21291525917107.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21291525917659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10645762958579 + 10645762958580.

It is an arithmetic number, because the mean of its divisors is an integer number (10645762958580).

Almost surely, 2^{21291525917159} is an apocalyptic number.

21291525917159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21291525917159 is an equidigital number, since it uses as much as digits as its factorization.

21291525917159 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5103000, while the sum is 59.

The spelling of 21291525917159 in words is "twenty-one trillion, two hundred ninety-one billion, five hundred twenty-five million, nine hundred seventeen thousand, one hundred fifty-nine".