5521564781 has 8 divisors (see below), whose sum is σ = 5531959800. Its totient is φ = 5511181312.

The previous prime is 5521564777. The next prime is 5521564831. The reversal of 5521564781 is 1874651255.

It can be written as a sum of positive squares in 4 ways, for example, as 2998110025 + 2523454756 = 54755^2 + 50234^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 5521564781 - 2² = 5521564777 is a prime.

It is a super-2 number, since 2×5521564781² = 60975355261559155922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5521564381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2164895 + ... + 2167443.

It is an arithmetic number, because the mean of its divisors is an integer number (691494975).

Almost surely, 2^5521564781 is an apocalyptic number.

It is an amenable number.

5521564781 is a deficient number, since it is larger than the sum of its proper divisors (10395019).

5521564781 is a wasteful number, since it uses less digits than its factorization.

5521564781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5775.

The product of its digits is 336000, while the sum is 44.

The square root of 5521564781 is about 74307.2323599796. The cubic root of 5521564781 is about 1767.4781647761.

The spelling of 5521564781 in words is "five billion, five hundred twenty-one million, five hundred sixty-four thousand, seven hundred eighty-one".