421508729 has 2 divisors, whose sum is σ = 421508730. Its totient is φ = 421508728.

The previous prime is 421508713. The next prime is 421508771. The reversal of 421508729 is 927805124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 406103104 + 15405625 = 20152^2 + 3925^2 .

It is a cyclic number.

It is not a de Polignac number, because 421508729 - 2⁴ = 421508713 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 421508692 and 421508701.

It is not a weakly prime, because it can be changed into another prime (421508779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210754364 + 210754365.

It is an arithmetic number, because the mean of its divisors is an integer number (210754365).

Almost surely, 2^421508729 is an apocalyptic number.

It is an amenable number.

421508729 is a deficient number, since it is larger than the sum of its proper divisors (1).

421508729 is an equidigital number, since it uses as much as digits as its factorization.

421508729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 38.

The square root of 421508729 is about 20530.6777530602. The cubic root of 421508729 is about 749.7828876742.

The spelling of 421508729 in words is "four hundred twenty-one million, five hundred eight thousand, seven hundred twenty-nine".