728762921 has 2 divisors, whose sum is σ = 728762922. Its totient is φ = 728762920.

The previous prime is 728762891. The next prime is 728762927. The reversal of 728762921 is 129267827.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 530657296 + 198105625 = 23036^2 + 14075^2 .

It is a cyclic number.

It is not a de Polignac number, because 728762921 - 2⁶ = 728762857 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (728762927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364381460 + 364381461.

It is an arithmetic number, because the mean of its divisors is an integer number (364381461).

Almost surely, 2^728762921 is an apocalyptic number.

It is an amenable number.

728762921 is a deficient number, since it is larger than the sum of its proper divisors (1).

728762921 is an equidigital number, since it uses as much as digits as its factorization.

728762921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 169344, while the sum is 44.

The square root of 728762921 is about 26995.6092911421. The cubic root of 728762921 is about 899.9024260474.

The spelling of 728762921 in words is "seven hundred twenty-eight million, seven hundred sixty-two thousand, nine hundred twenty-one".