405745121 has 4 divisors (see below), whose sum is σ = 408842544. Its totient is φ = 402647700.

The previous prime is 405745111. The next prime is 405745141. The reversal of 405745121 is 121547504.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 405745121 - 2¹⁴ = 405728737 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (405745111) 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, 1548515 + ... + 1548776.

It is an arithmetic number, because the mean of its divisors is an integer number (102210636).

Almost surely, 2^405745121 is an apocalyptic number.

It is an amenable number.

405745121 is a deficient number, since it is larger than the sum of its proper divisors (3097423).

405745121 is a wasteful number, since it uses less digits than its factorization.

405745121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3097422.

The product of its (nonzero) digits is 5600, while the sum is 29.

The square root of 405745121 is about 20143.1159704749. The cubic root of 405745121 is about 740.3170792373.

The spelling of 405745121 in words is "four hundred five million, seven hundred forty-five thousand, one hundred twenty-one".