2561015772 has 288 divisors, whose sum is σ = 8126576640. Its totient is φ = 694552320.

The previous prime is 2561015761. The next prime is 2561015777. The reversal of 2561015772 is 2775101652.

2561015772 is a `hidden beast` number, since 25 + 61 + 0 + 1 + 577 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561015777) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 10991368 + ... + 10991600.

It is an arithmetic number, because the mean of its divisors is an integer number (28217280).

Almost surely, 2^2561015772 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 2561015772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4063288320).

2561015772 is an abundant number, since it is smaller than the sum of its proper divisors (5565560868).

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

2561015772 is a wasteful number, since it uses less digits than its factorization.

2561015772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358 (or 343 counting only the distinct ones).

The product of its (nonzero) digits is 29400, while the sum is 36.

The square root of 2561015772 is about 50606.4795456076. The cubic root of 2561015772 is about 1368.1616652587.

The spelling of 2561015772 in words is "two billion, five hundred sixty-one million, fifteen thousand, seven hundred seventy-two".