1566420725 has 12 divisors (see below), whose sum is σ = 1943359620. Its totient is φ = 1252492800.

The previous prime is 1566420679. The next prime is 1566420733. The reversal of 1566420725 is 5270246651.

It can be written as a sum of positive squares in 6 ways, for example, as 116791249 + 1449629476 = 10807^2 + 38074^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1566420725 is a prime.

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 11 ways as a sum of consecutive naturals, for example, 36971 + ... + 67079.

It is an arithmetic number, because the mean of its divisors is an integer number (161946635).

Almost surely, 2^1566420725 is an apocalyptic number.

It is an amenable number.

1566420725 is a deficient number, since it is larger than the sum of its proper divisors (376938895).

1566420725 is a wasteful number, since it uses less digits than its factorization.

1566420725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32200 (or 32195 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 38.

The square root of 1566420725 is about 39578.0333644814. The cubic root of 1566420725 is about 1161.3669786986.

The spelling of 1566420725 in words is "one billion, five hundred sixty-six million, four hundred twenty thousand, seven hundred twenty-five".