1645136345 has 4 divisors (see below), whose sum is σ = 1974163620. Its totient is φ = 1316109072.

The previous prime is 1645136333. The next prime is 1645136351. The reversal of 1645136345 is 5436315461.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1189698064 + 455438281 = 34492^2 + 21341^2 .

It is a cyclic number.

It is not a de Polignac number, because 1645136345 - 2⁴ = 1645136329 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1645136299 and 1645136308.

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, 164513630 + ... + 164513639.

It is an arithmetic number, because the mean of its divisors is an integer number (493540905).

Almost surely, 2^1645136345 is an apocalyptic number.

It is an amenable number.

1645136345 is a deficient number, since it is larger than the sum of its proper divisors (329027275).

1645136345 is an equidigital number, since it uses as much as digits as its factorization.

1645136345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329027274.

The product of its digits is 129600, while the sum is 38.

The square root of 1645136345 is about 40560.2803861117. The cubic root of 1645136345 is about 1180.5035543534.

The spelling of 1645136345 in words is "one billion, six hundred forty-five million, one hundred thirty-six thousand, three hundred forty-five".