1645556256 has 192 divisors, whose sum is σ = 5140800000. Its totient is φ = 510541056.

The previous prime is 1645556249. The next prime is 1645556261. The reversal of 1645556256 is 6526555461.

1645556256 is a `hidden beast` number, since 1 + 6 + 45 + 556 + 2 + 56 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 967695 + ... + 969393.

It is an arithmetic number, because the mean of its divisors is an integer number (26775000).

Almost surely, 2^1645556256 is an apocalyptic number.

1645556256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1645556256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2570400000).

1645556256 is an abundant number, since it is smaller than the sum of its proper divisors (3495243744).

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

1645556256 is a wasteful number, since it uses less digits than its factorization.

1645556256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1796 (or 1782 counting only the distinct ones).

The product of its digits is 1080000, while the sum is 45.

The square root of 1645556256 is about 40565.4564377131. The cubic root of 1645556256 is about 1180.6039845822.

The spelling of 1645556256 in words is "one billion, six hundred forty-five million, five hundred fifty-six thousand, two hundred fifty-six".