1646263440 has 100 divisors (see below), whose sum is σ = 5717739324. Its totient is φ = 439001856.

The previous prime is 1646263427. The next prime is 1646263441. The reversal of 1646263440 is 443626461.

1646263440 is a `hidden beast` number, since 1 + 646 + 2 + 6 + 3 + 4 + 4 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 479084544 + 1167178896 = 21888^2 + 34164^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1646263395 and 1646263404.

It is not an unprimeable number, because it can be changed into a prime (1646263441) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 120547 + ... + 133506.

Almost surely, 2^1646263440 is an apocalyptic number.

1646263440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1646263440 is an abundant number, since it is smaller than the sum of its proper divisors (4071475884).

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

1646263440 is a wasteful number, since it uses less digits than its factorization.

1646263440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254078 (or 254063 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 36.

The square root of 1646263440 is about 40574.1720802779. The cubic root of 1646263440 is about 1180.7730833642.

The spelling of 1646263440 in words is "one billion, six hundred forty-six million, two hundred sixty-three thousand, four hundred forty".