402449581 has 2 divisors, whose sum is σ = 402449582. Its totient is φ = 402449580.

The previous prime is 402449557. The next prime is 402449591. The reversal of 402449581 is 185944204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 382789225 + 19660356 = 19565^2 + 4434^2 .

It is a cyclic number.

It is not a de Polignac number, because 402449581 - 2¹¹ = 402447533 is a prime.

It is a super-2 number, since 2×402449581² = 323931330494151122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 402449581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (402449521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201224790 + 201224791.

It is an arithmetic number, because the mean of its divisors is an integer number (201224791).

Almost surely, 2^402449581 is an apocalyptic number.

It is an amenable number.

402449581 is a deficient number, since it is larger than the sum of its proper divisors (1).

402449581 is an equidigital number, since it uses as much as digits as its factorization.

402449581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46080, while the sum is 37.

The square root of 402449581 is about 20061.1460540020. The cubic root of 402449581 is about 738.3072954700.

The spelling of 402449581 in words is "four hundred two million, four hundred forty-nine thousand, five hundred eighty-one".