1601856645 has 32 divisors (see below), whose sum is σ = 2689065984. Its totient is φ = 813196800.

The previous prime is 1601856629. The next prime is 1601856647. The reversal of 1601856645 is 5466581061.

It is not a de Polignac number, because 1601856645 - 2⁴ = 1601856629 is a prime.

It is a super-2 number, since 2×1601856645² = 5131889422261312050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1601856597 and 1601856606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601856647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129 + ... + 56601.

It is an arithmetic number, because the mean of its divisors is an integer number (84033312).

Almost surely, 2^1601856645 is an apocalyptic number.

1601856645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1601856645 is a deficient number, since it is larger than the sum of its proper divisors (1087209339).

1601856645 is a wasteful number, since it uses less digits than its factorization.

1601856645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56573.

The product of its (nonzero) digits is 172800, while the sum is 42.

The square root of 1601856645 is about 40023.2013337264. The cubic root of 1601856645 is about 1170.0593256498.

The spelling of 1601856645 in words is "one billion, six hundred one million, eight hundred fifty-six thousand, six hundred forty-five".