1645469916 has 48 divisors (see below), whose sum is σ = 4082268960. Its totient is φ = 514068480.

The previous prime is 1645469911. The next prime is 1645469921. The reversal of 1645469916 is 6199645461.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1645469911) and next prime (1645469921).

It is a super-2 number, since 2×1645469916² = 5415142488922094112, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645469911) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32430 + ... + 65898.

It is an arithmetic number, because the mean of its divisors is an integer number (85047270).

Almost surely, 2^1645469916 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1645469916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2041134480).

1645469916 is an abundant number, since it is smaller than the sum of its proper divisors (2436799044).

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

1645469916 is a wasteful number, since it uses less digits than its factorization.

1645469916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33734 (or 33732 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 51.

The square root of 1645469916 is about 40564.3922178060. The cubic root of 1645469916 is about 1180.5833360163.

The spelling of 1645469916 in words is "one billion, six hundred forty-five million, four hundred sixty-nine thousand, nine hundred sixteen".