172461721 has 2 divisors, whose sum is σ = 172461722. Its totient is φ = 172461720.

The previous prime is 172461713. The next prime is 172461749. The reversal of 172461721 is 127164271.

172461721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 160655625 + 11806096 = 12675^2 + 3436^2 .

It is a cyclic number.

It is not a de Polignac number, because 172461721 - 2³ = 172461713 is a prime.

It is a zygodrome in base 3.

It is not a weakly prime, because it can be changed into another prime (172461761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86230860 + 86230861.

It is an arithmetic number, because the mean of its divisors is an integer number (86230861).

Almost surely, 2^172461721 is an apocalyptic number.

It is an amenable number.

172461721 is a deficient number, since it is larger than the sum of its proper divisors (1).

172461721 is an equidigital number, since it uses as much as digits as its factorization.

172461721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4704, while the sum is 31.

The square root of 172461721 is about 13132.4681990858. The cubic root of 172461721 is about 556.6269614829.

The spelling of 172461721 in words is "one hundred seventy-two million, four hundred sixty-one thousand, seven hundred twenty-one".