31551121201 has 2 divisors, whose sum is σ = 31551121202. Its totient is φ = 31551121200.

The previous prime is 31551121187. The next prime is 31551121211. The reversal of 31551121201 is 10212115513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18605232801 + 12945888400 = 136401^2 + 113780^2 .

It is an emirp because it is prime and its reverse (10212115513) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31551121201 - 2¹¹ = 31551119153 is a prime.

It is not a weakly prime, because it can be changed into another prime (31551121211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15775560600 + 15775560601.

It is an arithmetic number, because the mean of its divisors is an integer number (15775560601).

Almost surely, 2^31551121201 is an apocalyptic number.

It is an amenable number.

31551121201 is a deficient number, since it is larger than the sum of its proper divisors (1).

31551121201 is an equidigital number, since it uses as much as digits as its factorization.

31551121201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 300, while the sum is 22.

Adding to 31551121201 its reverse (10212115513), we get a palindrome (41763236714).

The spelling of 31551121201 in words is "thirty-one billion, five hundred fifty-one million, one hundred twenty-one thousand, two hundred one".