1561272076 has 48 divisors (see below), whose sum is σ = 3368929536. Its totient is φ = 616509504.

The previous prime is 1561272067. The next prime is 1561272103. The reversal of 1561272076 is 6702721651.

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, 210015 + ... + 217321.

It is an arithmetic number, because the mean of its divisors is an integer number (70186032).

Almost surely, 2^1561272076 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 1561272076, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1684464768).

1561272076 is an abundant number, since it is smaller than the sum of its proper divisors (1807657460).

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

1561272076 is a wasteful number, since it uses less digits than its factorization.

1561272076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7918 (or 7916 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 37.

The square root of 1561272076 is about 39512.9355528035. The cubic root of 1561272076 is about 1160.0931544294.

It can be divided in two parts, 156127 and 2076, that added together give a triangular number (158203 = T₅₆₂).

The spelling of 1561272076 in words is "one billion, five hundred sixty-one million, two hundred seventy-two thousand, seventy-six".