561778251 has 8 divisors (see below), whose sum is σ = 749175504. Its totient is φ = 374449920.

The previous prime is 561778247. The next prime is 561778253. The reversal of 561778251 is 152877165.

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

It is not a de Polignac number, because 561778251 - 2² = 561778247 is a prime.

It is not an unprimeable number, because it can be changed into a prime (561778253) 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, 6435 + ... + 34131.

It is an arithmetic number, because the mean of its divisors is an integer number (93646938).

Almost surely, 2^561778251 is an apocalyptic number.

561778251 is a deficient number, since it is larger than the sum of its proper divisors (187397253).

561778251 is a wasteful number, since it uses less digits than its factorization.

561778251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34461.

The product of its digits is 117600, while the sum is 42.

The square root of 561778251 is about 23701.8617623173. The cubic root of 561778251 is about 825.1285999713.

The spelling of 561778251 in words is "five hundred sixty-one million, seven hundred seventy-eight thousand, two hundred fifty-one".