221752745206501 has 2 divisors, whose sum is σ = 221752745206502. Its totient is φ = 221752745206500.

The previous prime is 221752745206453. The next prime is 221752745206547. The reversal of 221752745206501 is 105602547257122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 185438321645476 + 36314423561025 = 13617574^2 + 6026145^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221752745206501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221752745206561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110876372603250 + 110876372603251.

It is an arithmetic number, because the mean of its divisors is an integer number (110876372603251).

Almost surely, 2^{221752745206501} is an apocalyptic number.

It is an amenable number.

221752745206501 is a deficient number, since it is larger than the sum of its proper divisors (1).

221752745206501 is an equidigital number, since it uses as much as digits as its factorization.

221752745206501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2352000, while the sum is 49.

The spelling of 221752745206501 in words is "two hundred twenty-one trillion, seven hundred fifty-two billion, seven hundred forty-five million, two hundred six thousand, five hundred one".