402142121 has 2 divisors, whose sum is σ = 402142122. Its totient is φ = 402142120.

The previous prime is 402142109. The next prime is 402142127. The reversal of 402142121 is 121241204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 342250000 + 59892121 = 18500^2 + 7739^2 .

It is a cyclic number.

It is not a de Polignac number, because 402142121 - 2⁶ = 402142057 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 402142121.

It is not a weakly prime, because it can be changed into another prime (402142127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201071060 + 201071061.

It is an arithmetic number, because the mean of its divisors is an integer number (201071061).

Almost surely, 2^402142121 is an apocalyptic number.

It is an amenable number.

402142121 is a deficient number, since it is larger than the sum of its proper divisors (1).

402142121 is an equidigital number, since it uses as much as digits as its factorization.

402142121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 402142121 is about 20053.4815181803. The cubic root of 402142121 is about 738.1192323324.

Adding to 402142121 its reverse (121241204), we get a palindrome (523383325).

The spelling of 402142121 in words is "four hundred two million, one hundred forty-two thousand, one hundred twenty-one".