1645815955 has 16 divisors (see below), whose sum is σ = 2260638720. Its totient is φ = 1126799712.

The previous prime is 1645815949. The next prime is 1645816001. The reversal of 1645815955 is 5595185461.

It is a cyclic number.

It is not a de Polignac number, because 1645815955 - 2⁵ = 1645815923 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1645815899 and 1645815908.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13695 + ... + 58984.

It is an arithmetic number, because the mean of its divisors is an integer number (141289920).

Almost surely, 2^1645815955 is an apocalyptic number.

1645815955 is a deficient number, since it is larger than the sum of its proper divisors (614822765).

1645815955 is an equidigital number, since it uses as much as digits as its factorization.

1645815955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73338.

The product of its digits is 1080000, while the sum is 49.

The square root of 1645815955 is about 40568.6572984613. The cubic root of 1645815955 is about 1180.6660883127. Note that the first 3 decimals are identical.

The spelling of 1645815955 in words is "one billion, six hundred forty-five million, eight hundred fifteen thousand, nine hundred fifty-five".