1909797945 has 32 divisors (see below), whose sum is σ = 3340237824. Its totient is φ = 924081600.

The previous prime is 1909797937. The next prime is 1909797961. The reversal of 1909797945 is 5497979091.

It is a happy number.

It is not a de Polignac number, because 1909797945 - 2³ = 1909797937 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71490 + ... + 94500.

It is an arithmetic number, because the mean of its divisors is an integer number (104382432).

Almost surely, 2^1909797945 is an apocalyptic number.

1909797945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1909797945 is a deficient number, since it is larger than the sum of its proper divisors (1430439879).

1909797945 is a wasteful number, since it uses less digits than its factorization.

1909797945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23533.

The product of its (nonzero) digits is 6429780, while the sum is 60.

The square root of 1909797945 is about 43701.2350511974. The cubic root of 1909797945 is about 1240.6876919467.

The spelling of 1909797945 in words is "one billion, nine hundred nine million, seven hundred ninety-seven thousand, nine hundred forty-five".