752720921 has 2 divisors, whose sum is σ = 752720922. Its totient is φ = 752720920.

The previous prime is 752720869. The next prime is 752720959. The reversal of 752720921 is 129027257.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 739840000 + 12880921 = 27200^2 + 3589^2 .

It is a cyclic number.

It is not a de Polignac number, because 752720921 - 2²² = 748526617 is a prime.

It is a super-3 number, since 3×752720921³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (752720981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 376360460 + 376360461.

It is an arithmetic number, because the mean of its divisors is an integer number (376360461).

Almost surely, 2^752720921 is an apocalyptic number.

It is an amenable number.

752720921 is a deficient number, since it is larger than the sum of its proper divisors (1).

752720921 is an equidigital number, since it uses as much as digits as its factorization.

752720921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17640, while the sum is 35.

The square root of 752720921 is about 27435.7598947068. The cubic root of 752720921 is about 909.6576907582.

The spelling of 752720921 in words is "seven hundred fifty-two million, seven hundred twenty thousand, nine hundred twenty-one".