421491157 has 2 divisors, whose sum is σ = 421491158. Its totient is φ = 421491156.

The previous prime is 421491143. The next prime is 421491173. The reversal of 421491157 is 751194124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 337603876 + 83887281 = 18374^2 + 9159^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421491157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (421491857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210745578 + 210745579.

It is an arithmetic number, because the mean of its divisors is an integer number (210745579).

Almost surely, 2^421491157 is an apocalyptic number.

It is an amenable number.

421491157 is a deficient number, since it is larger than the sum of its proper divisors (1).

421491157 is an equidigital number, since it uses as much as digits as its factorization.

421491157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 34.

The square root of 421491157 is about 20530.2498036434. The cubic root of 421491157 is about 749.7724684610.

The spelling of 421491157 in words is "four hundred twenty-one million, four hundred ninety-one thousand, one hundred fifty-seven".