1561835884 has 48 divisors (see below), whose sum is σ = 3281273856. Its totient is φ = 635976000.

The previous prime is 1561835857. The next prime is 1561835903. The reversal of 1561835884 is 4885381651.

It is a super-2 number, since 2×1561835884² = 4878662657100122912, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89214 + ... + 105274.

It is an arithmetic number, because the mean of its divisors is an integer number (68359872).

Almost surely, 2^1561835884 is an apocalyptic number.

1561835884 is a gapful number since it is divisible by the number (14) 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 1561835884, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1640636928).

1561835884 is an abundant number, since it is smaller than the sum of its proper divisors (1719437972).

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

1561835884 is a wasteful number, since it uses less digits than its factorization.

1561835884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16246 (or 16244 counting only the distinct ones).

The product of its digits is 921600, while the sum is 49.

The square root of 1561835884 is about 39520.0693825302. The cubic root of 1561835884 is about 1160.2327822569.

The spelling of 1561835884 in words is "one billion, five hundred sixty-one million, eight hundred thirty-five thousand, eight hundred eighty-four".