1215625645 has 8 divisors (see below), whose sum is σ = 1570962456. Its totient is φ = 897692736.

The previous prime is 1215625603. The next prime is 1215625667. The reversal of 1215625645 is 5465265121.

It can be written as a sum of positive squares in 4 ways, for example, as 142014889 + 1073610756 = 11917^2 + 32766^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1215625645 - 2¹⁷ = 1215494573 is a prime.

It is a super-3 number, since 3×1215625645³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9350902 + ... + 9351031.

It is an arithmetic number, because the mean of its divisors is an integer number (196370307).

Almost surely, 2^1215625645 is an apocalyptic number.

It is an amenable number.

1215625645 is a deficient number, since it is larger than the sum of its proper divisors (355336811).

1215625645 is a wasteful number, since it uses less digits than its factorization.

1215625645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18701951.

The product of its digits is 72000, while the sum is 37.

The square root of 1215625645 is about 34865.8234522003. The cubic root of 1215625645 is about 1067.2511165035.

The spelling of 1215625645 in words is "one billion, two hundred fifteen million, six hundred twenty-five thousand, six hundred forty-five".