1561059840 has 160 divisors (see below), whose sum is σ = 5022553536. Its totient is φ = 413614080.

The previous prime is 1561059811. The next prime is 1561059869. The reversal of 1561059840 is 489501651.

It is an interprime number because it is at equal distance from previous prime (1561059811) and next prime (1561059869).

It is a tau number, because it is divible by the number of its divisors (160).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1389519 + ... + 1390641.

Almost surely, 2^1561059840 is an apocalyptic number.

1561059840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561059840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2511276768).

1561059840 is an abundant number, since it is smaller than the sum of its proper divisors (3461493696).

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

1561059840 is a wasteful number, since it uses less digits than its factorization.

1561059840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1330 (or 1314 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 39.

The square root of 1561059840 is about 39510.2498093849. The cubic root of 1561059840 is about 1160.0405851833.

The spelling of 1561059840 in words is "one billion, five hundred sixty-one million, fifty-nine thousand, eight hundred forty".