421007731 has 2 divisors, whose sum is σ = 421007732. Its totient is φ = 421007730.

The previous prime is 421007701. The next prime is 421007747. The reversal of 421007731 is 137700124.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 421007731 - 2⁹ = 421007219 is a prime.

It is a super-2 number, since 2×421007731² = 354495019123536722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 421007696 and 421007705.

It is not a weakly prime, because it can be changed into another prime (421007701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210503865 + 210503866.

It is an arithmetic number, because the mean of its divisors is an integer number (210503866).

Almost surely, 2^421007731 is an apocalyptic number.

421007731 is a deficient number, since it is larger than the sum of its proper divisors (1).

421007731 is an equidigital number, since it uses as much as digits as its factorization.

421007731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 421007731 is about 20518.4729207609. The cubic root of 421007731 is about 749.4857102368.

Adding to 421007731 its reverse (137700124), we get a palindrome (558707855).

The spelling of 421007731 in words is "four hundred twenty-one million, seven thousand, seven hundred thirty-one".