2155120001 has 2 divisors, whose sum is σ = 2155120002. Its totient is φ = 2155120000.

The previous prime is 2155119991. The next prime is 2155120027. The reversal of 2155120001 is 1000215512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2154816400 + 303601 = 46420^2 + 551^2 .

It is a cyclic number.

It is not a de Polignac number, because 2155120001 - 2¹⁸ = 2154857857 is a prime.

It is not a weakly prime, because it can be changed into another prime (2155120091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077560000 + 1077560001.

It is an arithmetic number, because the mean of its divisors is an integer number (1077560001).

Almost surely, 2^2155120001 is an apocalyptic number.

It is an amenable number.

2155120001 is a deficient number, since it is larger than the sum of its proper divisors (1).

2155120001 is an equidigital number, since it uses as much as digits as its factorization.

2155120001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 2155120001 is about 46423.2700377731. The cubic root of 2155120001 is about 1291.6865948744.

Adding to 2155120001 its reverse (1000215512), we get a palindrome (3155335513).

The spelling of 2155120001 in words is "two billion, one hundred fifty-five million, one hundred twenty thousand, one".