1561501125 has 32 divisors (see below), whose sum is σ = 2887048320. Its totient is φ = 832798800.

The previous prime is 1561501099. The next prime is 1561501133. The reversal of 1561501125 is 5211051651.

1561501125 is a `hidden beast` number, since 15 + 615 + 0 + 11 + 25 = 666.

It is not a de Polignac number, because 1561501125 - 2¹⁷ = 1561370053 is a prime.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 227959 + ... + 234708.

It is an arithmetic number, because the mean of its divisors is an integer number (90220260).

Almost surely, 2^1561501125 is an apocalyptic number.

1561501125 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1561501125 is a deficient number, since it is larger than the sum of its proper divisors (1325547195).

1561501125 is an equidigital number, since it uses as much as digits as its factorization.

1561501125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462691 (or 462675 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 27.

The square root of 1561501125 is about 39515.8338517612. The cubic root of 1561501125 is about 1160.1498827831.

Adding to 1561501125 its reverse (5211051651), we get a palindrome (6772552776).

The spelling of 1561501125 in words is "one billion, five hundred sixty-one million, five hundred one thousand, one hundred twenty-five".