405725732161 has 4 divisors (see below), whose sum is σ = 405727202500. Its totient is φ = 405724261824.

The previous prime is 405725732147. The next prime is 405725732207. The reversal of 405725732161 is 161237527504.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 221422949136 + 184302783025 = 470556^2 + 429305^2 .

It is a cyclic number.

It is not a de Polignac number, because 405725732161 - 2²³ = 405717343553 is a prime.

It is a super-2 number, since 2×405725732161² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (405725732131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 183036 + ... + 919213.

It is an arithmetic number, because the mean of its divisors is an integer number (101431800625).

Almost surely, 2^405725732161 is an apocalyptic number.

It is an amenable number.

405725732161 is a deficient number, since it is larger than the sum of its proper divisors (1470339).

405725732161 is a wasteful number, since it uses less digits than its factorization.

405725732161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1470338.

The product of its (nonzero) digits is 352800, while the sum is 43.

The spelling of 405725732161 in words is "four hundred five billion, seven hundred twenty-five million, seven hundred thirty-two thousand, one hundred sixty-one".