402981421 has 2 divisors, whose sum is σ = 402981422. Its totient is φ = 402981420.

The previous prime is 402981407. The next prime is 402981451. The reversal of 402981421 is 124189204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 401802025 + 1179396 = 20045^2 + 1086^2 .

It is a cyclic number.

It is not a de Polignac number, because 402981421 - 2²¹ = 400884269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (402981451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201490710 + 201490711.

It is an arithmetic number, because the mean of its divisors is an integer number (201490711).

Almost surely, 2^402981421 is an apocalyptic number.

It is an amenable number.

402981421 is a deficient number, since it is larger than the sum of its proper divisors (1).

402981421 is an equidigital number, since it uses as much as digits as its factorization.

402981421 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 31.

The square root of 402981421 is about 20074.3971515959. The cubic root of 402981421 is about 738.6323784362.

The spelling of 402981421 in words is "four hundred two million, nine hundred eighty-one thousand, four hundred twenty-one".