402440551 has 2 divisors, whose sum is σ = 402440552. Its totient is φ = 402440550.

The previous prime is 402440513. The next prime is 402440557. The reversal of 402440551 is 155044204.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 402440551 - 2²¹ = 400343399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (402440557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201220275 + 201220276.

It is an arithmetic number, because the mean of its divisors is an integer number (201220276).

Almost surely, 2^402440551 is an apocalyptic number.

402440551 is a deficient number, since it is larger than the sum of its proper divisors (1).

402440551 is an equidigital number, since it uses as much as digits as its factorization.

402440551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3200, while the sum is 25.

The square root of 402440551 is about 20060.9209908219. The cubic root of 402440551 is about 738.3017734824.

Adding to 402440551 its reverse (155044204), we get a palindrome (557484755).

The spelling of 402440551 in words is "four hundred two million, four hundred forty thousand, five hundred fifty-one".