1663402500 has 240 divisors, whose sum is σ = 5676932800. Its totient is φ = 419904000.

The previous prime is 1663402493. The next prime is 1663402523. The reversal of 1663402500 is 52043661.

1663402500 is a `hidden beast` number, since 1 + 6 + 634 + 0 + 25 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1281852 + ... + 1283148.

Almost surely, 2^1663402500 is an apocalyptic number.

1663402500 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 1663402500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2838466400).

1663402500 is an abundant number, since it is smaller than the sum of its proper divisors (4013530300).

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

1663402500 is a wasteful number, since it uses less digits than its factorization.

1663402500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1349 (or 1326 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 1663402500 is about 40784.8317392631. The cubic root of 1663402500 is about 1184.8565761363.

The spelling of 1663402500 in words is "one billion, six hundred sixty-three million, four hundred two thousand, five hundred".