42403031021 has 6 divisors (see below), whose sum is σ = 45915708330. Its totient is φ = 39141259248.

The previous prime is 42403031009. The next prime is 42403031023. The reversal of 42403031021 is 12013030424.

It can be written as a sum of positive squares in 3 ways, for example, as 1483405225 + 40919625796 = 38515^2 + 202286^2 .

It is not a de Polignac number, because 42403031021 - 2²⁶ = 42335922157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42403030984 and 42403031002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42403031023) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 125452586 + ... + 125452923.

It is an arithmetic number, because the mean of its divisors is an integer number (7652618055).

Almost surely, 2^42403031021 is an apocalyptic number.

It is an amenable number.

42403031021 is a deficient number, since it is larger than the sum of its proper divisors (3512677309).

42403031021 is a wasteful number, since it uses less digits than its factorization.

42403031021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250905535 (or 250905522 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 42403031021 its reverse (12013030424), we get a palindrome (54416061445).

The spelling of 42403031021 in words is "forty-two billion, four hundred three million, thirty-one thousand, twenty-one".