1561503450 has 96 divisors (see below), whose sum is σ = 4272351552. Its totient is φ = 374976000.

The previous prime is 1561503439. The next prime is 1561503451. The reversal of 1561503450 is 543051651.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1561503451) 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, 70185 + ... + 89715.

It is an arithmetic number, because the mean of its divisors is an integer number (44503662).

Almost surely, 2^1561503450 is an apocalyptic number.

1561503450 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 1561503450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2136175776).

1561503450 is an abundant number, since it is smaller than the sum of its proper divisors (2710848102).

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

1561503450 is a wasteful number, since it uses less digits than its factorization.

1561503450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19600 (or 19595 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 30.

The square root of 1561503450 is about 39515.8632703374. The cubic root of 1561503450 is about 1160.1504585853.

The spelling of 1561503450 in words is "one billion, five hundred sixty-one million, five hundred three thousand, four hundred fifty".