42402004649 has 2 divisors, whose sum is σ = 42402004650. Its totient is φ = 42402004648.

The previous prime is 42402004621. The next prime is 42402004651. The reversal of 42402004649 is 94640020424.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34878177049 + 7523827600 = 186757^2 + 86740^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42402004649 is a prime.

It is a super-2 number, since 2×42402004649² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 42402004651, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (42402004609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21201002324 + 21201002325.

It is an arithmetic number, because the mean of its divisors is an integer number (21201002325).

Almost surely, 2^42402004649 is an apocalyptic number.

It is an amenable number.

42402004649 is a deficient number, since it is larger than the sum of its proper divisors (1).

42402004649 is an equidigital number, since it uses as much as digits as its factorization.

42402004649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 55296, while the sum is 35.

The spelling of 42402004649 in words is "forty-two billion, four hundred two million, four thousand, six hundred forty-nine".