31433042021 has 4 divisors (see below), whose sum is σ = 31433486700. Its totient is φ = 31432597344.

The previous prime is 31433041949. The next prime is 31433042059. The reversal of 31433042021 is 12024033413.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 26586933025 + 4846108996 = 163055^2 + 69614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31433042021 is a prime.

It is a super-2 number, since 2×31433042021² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31433044021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90086 + ... + 266423.

It is an arithmetic number, because the mean of its divisors is an integer number (7858371675).

Almost surely, 2^31433042021 is an apocalyptic number.

It is an amenable number.

31433042021 is a deficient number, since it is larger than the sum of its proper divisors (444679).

31433042021 is an equidigital number, since it uses as much as digits as its factorization.

31433042021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444678.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 31433042021 its reverse (12024033413), we get a palindrome (43457075434).

The spelling of 31433042021 in words is "thirty-one billion, four hundred thirty-three million, forty-two thousand, twenty-one".