3405209921 has 2 divisors, whose sum is σ = 3405209922. Its totient is φ = 3405209920.

The previous prime is 3405209897. The next prime is 3405209933. The reversal of 3405209921 is 1299025043.

3405209921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2974066225 + 431143696 = 54535^2 + 20764^2 .

It is a cyclic number.

It is not a de Polignac number, because 3405209921 - 2¹⁴ = 3405193537 is a prime.

It is not a weakly prime, because it can be changed into another prime (3405209971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1702604960 + 1702604961.

It is an arithmetic number, because the mean of its divisors is an integer number (1702604961).

Almost surely, 2^3405209921 is an apocalyptic number.

It is an amenable number.

3405209921 is a deficient number, since it is larger than the sum of its proper divisors (1).

3405209921 is an equidigital number, since it uses as much as digits as its factorization.

3405209921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 35.

The square root of 3405209921 is about 58354.1765514689. The cubic root of 3405209921 is about 1504.4622562018.

The spelling of 3405209921 in words is "three billion, four hundred five million, two hundred nine thousand, nine hundred twenty-one".