21225053315429 has 2 divisors, whose sum is σ = 21225053315430. Its totient is φ = 21225053315428.

The previous prime is 21225053315407. The next prime is 21225053315509. The reversal of 21225053315429 is 92451335052212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17054174308900 + 4170879006529 = 4129670^2 + 2042273^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21225053315429 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21225053315429.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21225053315729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612526657714 + 10612526657715.

It is an arithmetic number, because the mean of its divisors is an integer number (10612526657715).

Almost surely, 2^{21225053315429} is an apocalyptic number.

It is an amenable number.

21225053315429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225053315429 is an equidigital number, since it uses as much as digits as its factorization.

21225053315429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648000, while the sum is 44.

The spelling of 21225053315429 in words is "twenty-one trillion, two hundred twenty-five billion, fifty-three million, three hundred fifteen thousand, four hundred twenty-nine".