1900111721 has 8 divisors (see below), whose sum is σ = 1909670400. Its totient is φ = 1890567360.

The previous prime is 1900111711. The next prime is 1900111769. The reversal of 1900111721 is 1271110091.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1900111721 is a prime.

It is a super-2 number, since 2×1900111721² = 7220849104563163682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1900111711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 344060 + ... + 349538.

It is an arithmetic number, because the mean of its divisors is an integer number (238708800).

Almost surely, 2^1900111721 is an apocalyptic number.

It is an amenable number.

1900111721 is a deficient number, since it is larger than the sum of its proper divisors (9558679).

1900111721 is a wasteful number, since it uses less digits than its factorization.

1900111721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7159.

The product of its (nonzero) digits is 126, while the sum is 23.

The square root of 1900111721 is about 43590.2709443289. The cubic root of 1900111721 is about 1238.5866051933.

The spelling of 1900111721 in words is "one billion, nine hundred million, one hundred eleven thousand, seven hundred twenty-one".