21012120119971 has 2 divisors, whose sum is σ = 21012120119972. Its totient is φ = 21012120119970.

The previous prime is 21012120119933. The next prime is 21012120120001. The reversal of 21012120119971 is 17991102121012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21012120119971 - 2²⁵ = 21012086565539 is a prime.

It is a super-2 number, since 2×21012120119971² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21012120119971.

It is not a weakly prime, because it can be changed into another prime (21012120719971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506060059985 + 10506060059986.

It is an arithmetic number, because the mean of its divisors is an integer number (10506060059986).

Almost surely, 2^{21012120119971} is an apocalyptic number.

21012120119971 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012120119971 is an equidigital number, since it uses as much as digits as its factorization.

21012120119971 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 37.

The spelling of 21012120119971 in words is "twenty-one trillion, twelve billion, one hundred twenty million, one hundred nineteen thousand, nine hundred seventy-one".