1561327550 has 24 divisors (see below), whose sum is σ = 2905166736. Its totient is φ = 624295040.

The previous prime is 1561327531. The next prime is 1561327553. The reversal of 1561327550 is 557231651.

It is a self number, because there is not a number n which added to its sum of digits gives 1561327550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561327553) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 196454 + ... + 204246.

It is an arithmetic number, because the mean of its divisors is an integer number (121048614).

Almost surely, 2^1561327550 is an apocalyptic number.

1561327550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1561327550 is a deficient number, since it is larger than the sum of its proper divisors (1343839186).

1561327550 is a wasteful number, since it uses less digits than its factorization.

1561327550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11812 (or 11807 counting only the distinct ones).

The product of its (nonzero) digits is 31500, while the sum is 35.

The square root of 1561327550 is about 39513.6375192161. The cubic root of 1561327550 is about 1160.1068941327.

The spelling of 1561327550 in words is "one billion, five hundred sixty-one million, three hundred twenty-seven thousand, five hundred fifty".