55212331 has 2 divisors, whose sum is σ = 55212332. Its totient is φ = 55212330.

The previous prime is 55212299. The next prime is 55212343. The reversal of 55212331 is 13321255.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 55212331 - 2⁵ = 55212299 is a prime.

It is a super-2 number, since 2×55212331² = 6096802988907122, which contains 22 as substring.

It is the 7431-st Hogben number.

It is not a weakly prime, because it can be changed into another prime (55212631) by changing a digit.

It is a nontrivial repunit in base 7430.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27606165 + 27606166.

It is an arithmetic number, because the mean of its divisors is an integer number (27606166).

Almost surely, 2^55212331 is an apocalyptic number.

55212331 is a deficient number, since it is larger than the sum of its proper divisors (1).

55212331 is an equidigital number, since it uses as much as digits as its factorization.

55212331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 900, while the sum is 22.

The square root of 55212331 is about 7430.5000504677. The cubic root of 55212331 is about 380.7840023225.

Adding to 55212331 its reverse (13321255), we get a palindrome (68533586).

The spelling of 55212331 in words is "fifty-five million, two hundred twelve thousand, three hundred thirty-one".