1645942400 has 48 divisors (see below), whose sum is σ = 4065999990. Its totient is φ = 658375680.

The previous prime is 1645942297. The next prime is 1645942409. The reversal of 1645942400 is 42495461.

It can be written as a sum of positive squares in 3 ways, for example, as 1525996096 + 119946304 = 39064^2 + 10952^2 .

It is a super-3 number, since 3×1645942400³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1645942409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 253979 + ... + 260378.

Almost surely, 2^1645942400 is an apocalyptic number.

1645942400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1645942400 is an abundant number, since it is smaller than the sum of its proper divisors (2420057590).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1645942400 is an equidigital number, since it uses as much as digits as its factorization.

1645942400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514381 (or 514364 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 1645942400 is about 40570.2156760350. The cubic root of 1645942400 is about 1180.6963236700.

The spelling of 1645942400 in words is "one billion, six hundred forty-five million, nine hundred forty-two thousand, four hundred".