1900945 has 4 divisors (see below), whose sum is σ = 2281140. Its totient is φ = 1520752.

The previous prime is 1900937. The next prime is 1900981. The reversal of 1900945 is 5490091.

1900945 is nontrivially palindromic in base 6.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5490091 = 401 ⋅13691.

It can be written as a sum of positive squares in 2 ways, for example, as 571536 + 1329409 = 756^2 + 1153^2 .

It is a cyclic number.

It is not a de Polignac number, because 1900945 - 2³ = 1900937 is a prime.

It is a super-2 number, since 2×1900945² = 7227183786050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190090 + ... + 190099.

It is an arithmetic number, because the mean of its divisors is an integer number (570285).

2^1900945 is an apocalyptic number.

It is an amenable number.

1900945 is a deficient number, since it is larger than the sum of its proper divisors (380195).

1900945 is an equidigital number, since it uses as much as digits as its factorization.

1900945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380194.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 1900945 is about 1378.7476201249. The cubic root of 1900945 is about 123.8767636193.

The spelling of 1900945 in words is "one million, nine hundred thousand, nine hundred forty-five".