561397650 has 72 divisors (see below), whose sum is σ = 1530391632. Its totient is φ = 136092000.

The previous prime is 561397619. The next prime is 561397651. The reversal of 561397650 is 56793165.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (561397651) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2685 + ... + 33615.

Almost surely, 2^561397650 is an apocalyptic number.

561397650 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 561397650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (765195816).

561397650 is an abundant number, since it is smaller than the sum of its proper divisors (968993982).

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

561397650 is a wasteful number, since it uses less digits than its factorization.

561397650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30968 (or 30952 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 42.

The square root of 561397650 is about 23693.8314757238. The cubic root of 561397650 is about 824.9422181754.

The spelling of 561397650 in words is "five hundred sixty-one million, three hundred ninety-seven thousand, six hundred fifty".