1561125312 has 168 divisors, whose sum is σ = 4767586096. Its totient is φ = 506124288.

The previous prime is 1561125287. The next prime is 1561125331. The reversal of 1561125312 is 2135211651.

1561125312 is a `hidden beast` number, since 15 + 6 + 112 + 531 + 2 = 666.

It is a super-2 number, since 2×1561125312² = 4874224479534194688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 574068 + ... + 576780.

Almost surely, 2^1561125312 is an apocalyptic number.

1561125312 is a gapful number since it is divisible by the number (12) 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 1561125312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2383793048).

1561125312 is an abundant number, since it is smaller than the sum of its proper divisors (3206460784).

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

1561125312 is an equidigital number, since it uses as much as digits as its factorization.

1561125312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2777 (or 2755 counting only the distinct ones).

The product of its digits is 1800, while the sum is 27.

The square root of 1561125312 is about 39511.0783451933. The cubic root of 1561125312 is about 1160.0568026089.

Adding to 1561125312 its reverse (2135211651), we get a palindrome (3696336963).

The spelling of 1561125312 in words is "one billion, five hundred sixty-one million, one hundred twenty-five thousand, three hundred twelve".