21142120429 has 2 divisors, whose sum is σ = 21142120430. Its totient is φ = 21142120428.

The previous prime is 21142120411. The next prime is 21142120463. The reversal of 21142120429 is 92402124112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17213964804 + 3928155625 = 131202^2 + 62675^2 .

It is a cyclic number.

It is not a de Polignac number, because 21142120429 - 2³¹ = 18994636781 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21142120397 and 21142120406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21142120529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571060214 + 10571060215.

It is an arithmetic number, because the mean of its divisors is an integer number (10571060215).

Almost surely, 2^21142120429 is an apocalyptic number.

It is an amenable number.

21142120429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142120429 is an equidigital number, since it uses as much as digits as its factorization.

21142120429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 28.

The spelling of 21142120429 in words is "twenty-one billion, one hundred forty-two million, one hundred twenty thousand, four hundred twenty-nine".