1900889909 has 2 divisors, whose sum is σ = 1900889910. Its totient is φ = 1900889908.

The previous prime is 1900889849. The next prime is 1900889953. The reversal of 1900889909 is 9099880091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1617809284 + 283080625 = 40222^2 + 16825^2 .

It is an emirp because it is prime and its reverse (9099880091) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1900889909 is a prime.

It is a super-2 number, since 2×1900889909² = 7226764892276056562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1900889609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 950444954 + 950444955.

It is an arithmetic number, because the mean of its divisors is an integer number (950444955).

Almost surely, 2^1900889909 is an apocalyptic number.

It is an amenable number.

1900889909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1900889909 is an equidigital number, since it uses as much as digits as its factorization.

1900889909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 419904, while the sum is 53.

The square root of 1900889909 is about 43599.1961967190. The cubic root of 1900889909 is about 1238.7556692315.

The spelling of 1900889909 in words is "one billion, nine hundred million, eight hundred eighty-nine thousand, nine hundred nine".