1900121211001 has 32 divisors (see below), whose sum is σ = 2132407620000. Its totient is φ = 1681041911808.

The previous prime is 1900121210957. The next prime is 1900121211007. The reversal of 1900121211001 is 1001121210091.

It can be written as a sum of positive squares in 16 ways, for example, as 976025443600 + 924095767401 = 987940^2 + 961299^2 .

It is a cyclic number.

It is not a de Polignac number, because 1900121211001 - 2¹³ = 1900121202809 is a prime.

It is a super-2 number, since 2×1900121211001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1900121211001.

It is not an unprimeable number, because it can be changed into a prime (1900121211007) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 95989761 + ... + 96009553.

It is an arithmetic number, because the mean of its divisors is an integer number (66637738125).

Almost surely, 2^{1900121211001} is an apocalyptic number.

It is an amenable number.

1900121211001 is a deficient number, since it is larger than the sum of its proper divisors (232286408999).

1900121211001 is a wasteful number, since it uses less digits than its factorization.

1900121211001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21693.

The product of its (nonzero) digits is 36, while the sum is 19.

Adding to 1900121211001 its reverse (1001121210091), we get a palindrome (2901242421092).

The spelling of 1900121211001 in words is "one trillion, nine hundred billion, one hundred twenty-one million, two hundred eleven thousand, one".