221625311873429 has 2 divisors, whose sum is σ = 221625311873430. Its totient is φ = 221625311873428.

The previous prime is 221625311873351. The next prime is 221625311873467. The reversal of 221625311873429 is 924378113526122.

221625311873429 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138682890376900 + 82942421496529 = 11776370^2 + 9107273^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221625311873429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221625311803429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110812655936714 + 110812655936715.

It is an arithmetic number, because the mean of its divisors is an integer number (110812655936715).

Almost surely, 2^{221625311873429} is an apocalyptic number.

It is an amenable number.

221625311873429 is a deficient number, since it is larger than the sum of its proper divisors (1).

221625311873429 is an equidigital number, since it uses as much as digits as its factorization.

221625311873429 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8709120, while the sum is 56.

The spelling of 221625311873429 in words is "two hundred twenty-one trillion, six hundred twenty-five billion, three hundred eleven million, eight hundred seventy-three thousand, four hundred twenty-nine".