1646561376 has 36 divisors (see below), whose sum is σ = 4682409732. Its totient is φ = 548853696.

The previous prime is 1646561359. The next prime is 1646561417. The reversal of 1646561376 is 6731656461.

1646561376 is a `hidden beast` number, since 16 + 4 + 6 + 561 + 3 + 76 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×1646561376² = 5422328729870026752, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2858326 + ... + 2858901.

It is an arithmetic number, because the mean of its divisors is an integer number (130066937).

Almost surely, 2^1646561376 is an apocalyptic number.

1646561376 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1646561376 is an abundant number, since it is smaller than the sum of its proper divisors (3035848356).

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

1646561376 is a wasteful number, since it uses less digits than its factorization.

1646561376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5717243 (or 5717232 counting only the distinct ones).

The product of its digits is 544320, while the sum is 45.

The square root of 1646561376 is about 40577.8434123845. The cubic root of 1646561376 is about 1180.8443100344.

It can be divided in two parts, 16465 and 61376, that added together give a square (77841 = 279²).

The spelling of 1646561376 in words is "one billion, six hundred forty-six million, five hundred sixty-one thousand, three hundred seventy-six".