1561299516 has 192 divisors, whose sum is σ = 5019356160. Its totient is φ = 409466880.

The previous prime is 1561299497. The next prime is 1561299577. The reversal of 1561299516 is 6159921651.

It is a happy number.

1561299516 is a `hidden beast` number, since 1 + 5 + 6 + 129 + 9 + 516 = 666.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 525451 + ... + 528413.

It is an arithmetic number, because the mean of its divisors is an integer number (26142480).

Almost surely, 2^1561299516 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561299516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2509678080).

1561299516 is an abundant number, since it is smaller than the sum of its proper divisors (3458056644).

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

1561299516 is a wasteful number, since it uses less digits than its factorization.

1561299516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3041 (or 3033 counting only the distinct ones).

The product of its digits is 145800, while the sum is 45.

The square root of 1561299516 is about 39513.2827793389. The cubic root of 1561299516 is about 1160.0999507613.

The spelling of 1561299516 in words is "one billion, five hundred sixty-one million, two hundred ninety-nine thousand, five hundred sixteen".