1561024940 has 24 divisors (see below), whose sum is σ = 3307167360. Its totient is φ = 618883328.

The previous prime is 1561024937. The next prime is 1561024961. The reversal of 1561024940 is 494201651.

It is a junction number, because it is equal to n+sod(n) for n = 1561024897 and 1561024906.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 343100 + ... + 347619.

It is an arithmetic number, because the mean of its divisors is an integer number (137798640).

Almost surely, 2^1561024940 is an apocalyptic number.

1561024940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1561024940 is an abundant number, since it is smaller than the sum of its proper divisors (1746142420).

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

1561024940 is a wasteful number, since it uses less digits than its factorization.

1561024940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690841 (or 690839 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 1561024940 is about 39509.8081493697. The cubic root of 1561024940 is about 1160.0319402620.

The spelling of 1561024940 in words is "one billion, five hundred sixty-one million, twenty-four thousand, nine hundred forty".