1897473109 has 24 divisors (see below), whose sum is σ = 2271674808. Its totient is φ = 1579132800.

The previous prime is 1897473089. The next prime is 1897473119. The reversal of 1897473109 is 9013747981.

It can be written as a sum of positive squares in 4 ways, for example, as 1400406084 + 497067025 = 37422^2 + 22295^2 .

It is not a de Polignac number, because 1897473109 - 2⁵ = 1897473077 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1897473119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1270167 + ... + 1271659.

It is an arithmetic number, because the mean of its divisors is an integer number (94653117).

Almost surely, 2^1897473109 is an apocalyptic number.

It is an amenable number.

1897473109 is a deficient number, since it is larger than the sum of its proper divisors (374201699).

1897473109 is a wasteful number, since it uses less digits than its factorization.

1897473109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2245 (or 2238 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 49.

The square root of 1897473109 is about 43559.9943640951. The cubic root of 1897473109 is about 1238.0130137573.

The spelling of 1897473109 in words is "one billion, eight hundred ninety-seven million, four hundred seventy-three thousand, one hundred nine".