2101213191 has 64 divisors (see below), whose sum is σ = 3563191296. Its totient is φ = 1069824000.

The previous prime is 2101213123. The next prime is 2101213237. The reversal of 2101213191 is 1913121012.

2101213191 = 4021² + 4022² + ... + 4146².

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-2101213191 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101218191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2636005 + ... + 2636801.

It is an arithmetic number, because the mean of its divisors is an integer number (55674864).

Almost surely, 2^2101213191 is an apocalyptic number.

2101213191 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

2101213191 is a deficient number, since it is larger than the sum of its proper divisors (1461978105).

2101213191 is a wasteful number, since it uses less digits than its factorization.

2101213191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1032.

The product of its (nonzero) digits is 108, while the sum is 21.

The square root of 2101213191 is about 45838.9920373474. The cubic root of 2101213191 is about 1280.8257186446.

It can be divided in two parts, 210121 and 3191, that added together give a palindrome (213312).

The spelling of 2101213191 in words is "two billion, one hundred one million, two hundred thirteen thousand, one hundred ninety-one".