721421003 has 2 divisors, whose sum is σ = 721421004. Its totient is φ = 721421002.

The previous prime is 721420951. The next prime is 721421009. The reversal of 721421003 is 300124127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721421003 - 2⁶ = 721420939 is a prime.

It is not a weakly prime, because it can be changed into another prime (721421009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360710501 + 360710502.

It is an arithmetic number, because the mean of its divisors is an integer number (360710502).

Almost surely, 2^721421003 is an apocalyptic number.

721421003 is a deficient number, since it is larger than the sum of its proper divisors (1).

721421003 is an equidigital number, since it uses as much as digits as its factorization.

721421003 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 721421003 is about 26859.2815056546. The cubic root of 721421003 is about 896.8701997550.

The spelling of 721421003 in words is "seven hundred twenty-one million, four hundred twenty-one thousand, three".