3729431221 has 2 divisors, whose sum is σ = 3729431222. Its totient is φ = 3729431220.

The previous prime is 3729431171. The next prime is 3729431249. The reversal of 3729431221 is 1221349273.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3501088900 + 228342321 = 59170^2 + 15111^2 .

It is a cyclic number.

It is not a de Polignac number, because 3729431221 - 2¹⁹ = 3728906933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3729431521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1864715610 + 1864715611.

It is an arithmetic number, because the mean of its divisors is an integer number (1864715611).

Almost surely, 2^3729431221 is an apocalyptic number.

It is an amenable number.

3729431221 is a deficient number, since it is larger than the sum of its proper divisors (1).

3729431221 is an equidigital number, since it uses as much as digits as its factorization.

3729431221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 34.

The square root of 3729431221 is about 61069.0692658730. The cubic root of 3729431221 is about 1550.7705112584.

The spelling of 3729431221 in words is "three billion, seven hundred twenty-nine million, four hundred thirty-one thousand, two hundred twenty-one".