1561006500 has 48 divisors (see below), whose sum is σ = 4545655296. Its totient is φ = 416268000.

The previous prime is 1561006471. The next prime is 1561006537. The reversal of 1561006500 is 56001651.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 518836 + ... + 521835.

It is an arithmetic number, because the mean of its divisors is an integer number (94701152).

Almost surely, 2^1561006500 is an apocalyptic number.

1561006500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1561006500 is an abundant number, since it is smaller than the sum of its proper divisors (2984648796).

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

1561006500 is a wasteful number, since it uses less digits than its factorization.

1561006500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1040693 (or 1040681 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 1561006500 is about 39509.5747889040. The cubic root of 1561006500 is about 1160.0273725210.

The spelling of 1561006500 in words is "one billion, five hundred sixty-one million, six thousand, five hundred".