406981 has 2 divisors, whose sum is σ = 406982. Its totient is φ = 406980.

The previous prime is 406969. The next prime is 406993. The reversal of 406981 is 189604.

It is a balanced prime because it is at equal distance from previous prime (406969) and next prime (406993).

It can be written as a sum of positive squares in only one way, i.e., 370881 + 36100 = 609^2 + 190^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-406981 is a prime.

It is a super-2 number, since 2×406981² = 331267068722, which contains 22 as substring.

It is a Chen prime.

406981 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (406951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203490 + 203491.

It is an arithmetic number, because the mean of its divisors is an integer number (203491).

2⁴⁰⁶⁹⁸¹ is an apocalyptic number.

It is an amenable number.

406981 is a deficient number, since it is larger than the sum of its proper divisors (1).

406981 is an equidigital number, since it uses as much as digits as its factorization.

406981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 406981 is about 637.9506250487. The cubic root of 406981 is about 74.1067973413.

It can be divided in two parts, 40 and 6981, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 406981 in words is "four hundred six thousand, nine hundred eighty-one".