421145531 has 2 divisors, whose sum is σ = 421145532. Its totient is φ = 421145530.

The previous prime is 421145513. The next prime is 421145561. The reversal of 421145531 is 135541124.

Together with previous prime (421145513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 421145531 - 2⁶ = 421145467 is a prime.

It is a super-2 number, since 2×421145531² = 354727116562543922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 421145531.

It is not a weakly prime, because it can be changed into another prime (421145561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210572765 + 210572766.

It is an arithmetic number, because the mean of its divisors is an integer number (210572766).

Almost surely, 2^421145531 is an apocalyptic number.

421145531 is a deficient number, since it is larger than the sum of its proper divisors (1).

421145531 is an equidigital number, since it uses as much as digits as its factorization.

421145531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2400, while the sum is 26.

The square root of 421145531 is about 20521.8305957339. The cubic root of 421145531 is about 749.5674726822.

Adding to 421145531 its reverse (135541124), we get a palindrome (556686655).

The spelling of 421145531 in words is "four hundred twenty-one million, one hundred forty-five thousand, five hundred thirty-one".