1561189380 has 48 divisors (see below), whose sum is σ = 4376742720. Its totient is φ = 415801728.

The previous prime is 1561189379. The next prime is 1561189381. The reversal of 1561189380 is 839811651.

It is an interprime number because it is at equal distance from previous prime (1561189379) and next prime (1561189381).

It is not an unprimeable number, because it can be changed into a prime (1561189381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34047 + ... + 65433.

It is an arithmetic number, because the mean of its divisors is an integer number (91182140).

Almost surely, 2^1561189380 is an apocalyptic number.

1561189380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1561189380 is an abundant number, since it is smaller than the sum of its proper divisors (2815553340).

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

1561189380 is a wasteful number, since it uses less digits than its factorization.

1561189380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32228 (or 32226 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 1561189380 is about 39511.8890968276. The cubic root of 1561189380 is about 1160.0726718245.

The spelling of 1561189380 in words is "one billion, five hundred sixty-one million, one hundred eighty-nine thousand, three hundred eighty".