406678187581 has 2 divisors, whose sum is σ = 406678187582. Its totient is φ = 406678187580.

The previous prime is 406678187563. The next prime is 406678187599. The reversal of 406678187581 is 185781876604.

It is a balanced prime because it is at equal distance from previous prime (406678187563) and next prime (406678187599).

It can be written as a sum of positive squares in only one way, i.e., 405216272356 + 1461915225 = 636566^2 + 38235^2 .

It is a cyclic number.

It is not a de Polignac number, because 406678187581 - 2⁷ = 406678187453 is a prime.

It is a super-2 number, since 2×406678187581² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (406678187551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203339093790 + 203339093791.

It is an arithmetic number, because the mean of its divisors is an integer number (203339093791).

Almost surely, 2^406678187581 is an apocalyptic number.

It is an amenable number.

406678187581 is a deficient number, since it is larger than the sum of its proper divisors (1).

406678187581 is an equidigital number, since it uses as much as digits as its factorization.

406678187581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18063360, while the sum is 61.

The spelling of 406678187581 in words is "four hundred six billion, six hundred seventy-eight million, one hundred eighty-seven thousand, five hundred eighty-one".