2561421492 has 108 divisors (see below), whose sum is σ = 7547956416. Its totient is φ = 730265760.

The previous prime is 2561421481. The next prime is 2561421539. The reversal of 2561421492 is 2941241652.

It is a happy number.

2561421492 is a `hidden beast` number, since 2 + 561 + 4 + 2 + 1 + 4 + 92 = 666.

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

It is a congruent number.

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 35 ways as a sum of consecutive naturals, for example, 1005973 + ... + 1008515.

Almost surely, 2^2561421492 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 2561421492, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3773978208).

2561421492 is an abundant number, since it is smaller than the sum of its proper divisors (4986534924).

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

2561421492 is a wasteful number, since it uses less digits than its factorization.

2561421492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3138 (or 3126 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 2561421492 is about 50610.4879644526. The cubic root of 2561421492 is about 1368.2339101919.

The spelling of 2561421492 in words is "two billion, five hundred sixty-one million, four hundred twenty-one thousand, four hundred ninety-two".