418981021 has 2 divisors, whose sum is σ = 418981022. Its totient is φ = 418981020.

The previous prime is 418980973. The next prime is 418981039. The reversal of 418981021 is 120189814.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 414936900 + 4044121 = 20370^2 + 2011^2 .

It is a cyclic number.

It is not a de Polignac number, because 418981021 - 2²⁵ = 385426589 is a prime.

It is equal to p_22293385 and since 418981021 and 22293385 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (418981051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 209490510 + 209490511.

It is an arithmetic number, because the mean of its divisors is an integer number (209490511).

Almost surely, 2^418981021 is an apocalyptic number.

It is an amenable number.

418981021 is a deficient number, since it is larger than the sum of its proper divisors (1).

418981021 is an equidigital number, since it uses as much as digits as its factorization.

418981021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 34.

The square root of 418981021 is about 20469.0258927971. The cubic root of 418981021 is about 748.2811130613.

The spelling of 418981021 in words is "four hundred eighteen million, nine hundred eighty-one thousand, twenty-one".