15561630 has 96 divisors (see below), whose sum is σ = 48993984. Its totient is φ = 3345408.

The previous prime is 15561619. The next prime is 15561631. The reversal of 15561630 is 3616551.

It is a happy number.

15561630 is a `hidden beast` number, since 15 + 5 + 616 + 30 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 15561594 and 15561603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15561631) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9984 + ... + 11436.

It is an arithmetic number, because the mean of its divisors is an integer number (510354).

Almost surely, 2^15561630 is an apocalyptic number.

15561630 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 15561630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24496992).

15561630 is an abundant number, since it is smaller than the sum of its proper divisors (33432354).

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

15561630 is a wasteful number, since it uses less digits than its factorization.

15561630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1490 (or 1487 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 15561630 is about 3944.8231899541. The cubic root of 15561630 is about 249.6615687305.

The spelling of 15561630 in words is "fifteen million, five hundred sixty-one thousand, six hundred thirty".