406785381 has 4 divisors (see below), whose sum is σ = 542380512. Its totient is φ = 271190252.

The previous prime is 406785361. The next prime is 406785389. The reversal of 406785381 is 183587604.

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 406785381 - 2¹⁴ = 406768997 is a prime.

It is a super-2 number, since 2×406785381² = 330948692390630322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406785389) 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, 67797561 + ... + 67797566.

It is an arithmetic number, because the mean of its divisors is an integer number (135595128).

Almost surely, 2^406785381 is an apocalyptic number.

It is an amenable number.

406785381 is a deficient number, since it is larger than the sum of its proper divisors (135595131).

406785381 is a wasteful number, since it uses less digits than its factorization.

406785381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135595130.

The product of its (nonzero) digits is 161280, while the sum is 42.

The square root of 406785381 is about 20168.9211659920. The cubic root of 406785381 is about 740.9492207695.

The spelling of 406785381 in words is "four hundred six million, seven hundred eighty-five thousand, three hundred eighty-one".