1663649520 has 120 divisors (see below), whose sum is σ = 5584682736. Its totient is φ = 409503744.

The previous prime is 1663649509. The next prime is 1663649521. The reversal of 1663649520 is 259463661.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663649521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20052 + ... + 61068.

Almost surely, 2^1663649520 is an apocalyptic number.

1663649520 is a gapful number since it is divisible by the number (10) 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 1663649520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2792341368).

1663649520 is an abundant number, since it is smaller than the sum of its proper divisors (3921033216).

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

1663649520 is a wasteful number, since it uses less digits than its factorization.

1663649520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41059 (or 41040 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 42.

The square root of 1663649520 is about 40787.8599585710. The cubic root of 1663649520 is about 1184.9152247566.

The spelling of 1663649520 in words is "one billion, six hundred sixty-three million, six hundred forty-nine thousand, five hundred twenty".