191022401 has 2 divisors, whose sum is σ = 191022402. Its totient is φ = 191022400.

The previous prime is 191022397. The next prime is 191022407. The reversal of 191022401 is 104220191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 125978176 + 65044225 = 11224^2 + 8065^2 .

It is a cyclic number.

It is not a de Polignac number, because 191022401 - 2² = 191022397 is a prime.

It is not a weakly prime, because it can be changed into another prime (191022407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95511200 + 95511201.

It is an arithmetic number, because the mean of its divisors is an integer number (95511201).

Almost surely, 2^191022401 is an apocalyptic number.

It is an amenable number.

191022401 is a deficient number, since it is larger than the sum of its proper divisors (1).

191022401 is an equidigital number, since it uses as much as digits as its factorization.

191022401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 191022401 is about 13821.0853770607. The cubic root of 191022401 is about 575.9190354065.

Adding to 191022401 its reverse (104220191), we get a palindrome (295242592).

The spelling of 191022401 in words is "one hundred ninety-one million, twenty-two thousand, four hundred one".