1561125104 has 120 divisors (see below), whose sum is σ = 3866167728. Its totient is φ = 603832320.

The previous prime is 1561125043. The next prime is 1561125107. The reversal of 1561125104 is 4015211651.

It is a super-2 number, since 2×1561125104² = 4874223180678021632, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561125107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1353392 + ... + 1354544.

Almost surely, 2^1561125104 is an apocalyptic number.

1561125104 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561125104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1933083864).

1561125104 is an abundant number, since it is smaller than the sum of its proper divisors (2305042624).

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

1561125104 is a wasteful number, since it uses less digits than its factorization.

1561125104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1343 (or 1330 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 26.

The square root of 1561125104 is about 39511.0757130200. The cubic root of 1561125104 is about 1160.0567510879.

Adding to 1561125104 its reverse (4015211651), we get a palindrome (5576336755).

The spelling of 1561125104 in words is "one billion, five hundred sixty-one million, one hundred twenty-five thousand, one hundred four".