42212531 has 2 divisors, whose sum is σ = 42212532. Its totient is φ = 42212530.

The previous prime is 42212501. The next prime is 42212543. The reversal of 42212531 is 13521224.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42212531 is a prime.

It is a super-2 number, since 2×42212531² = 3563795546851922, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (42212501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21106265 + 21106266.

It is an arithmetic number, because the mean of its divisors is an integer number (21106266).

Almost surely, 2^42212531 is an apocalyptic number.

42212531 is a deficient number, since it is larger than the sum of its proper divisors (1).

42212531 is an equidigital number, since it uses as much as digits as its factorization.

42212531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 480, while the sum is 20.

The square root of 42212531 is about 6497.1171299277. The cubic root of 42212531 is about 348.1879984554.

Adding to 42212531 its reverse (13521224), we get a palindrome (55733755).

The spelling of 42212531 in words is "forty-two million, two hundred twelve thousand, five hundred thirty-one".