191421801 has 12 divisors (see below), whose sum is σ = 288520128. Its totient is φ = 122065944.

The previous prime is 191421793. The next prime is 191421803. The reversal of 191421801 is 108124191.

It is not a de Polignac number, because 191421801 - 2³ = 191421793 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (191421803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 462165 + ... + 462578.

It is an arithmetic number, because the mean of its divisors is an integer number (24043344).

Almost surely, 2^191421801 is an apocalyptic number.

It is an amenable number.

191421801 is a deficient number, since it is larger than the sum of its proper divisors (97098327).

191421801 is a wasteful number, since it uses less digits than its factorization.

191421801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 924772 (or 924769 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 191421801 is about 13835.5267698776. The cubic root of 191421801 is about 576.3201435719.

Adding to 191421801 its reverse (108124191), we get a palindrome (299545992).

The spelling of 191421801 in words is "one hundred ninety-one million, four hundred twenty-one thousand, eight hundred one".