1561418040 has 384 divisors, whose sum is σ = 6147394560. Its totient is φ = 309583872.

The previous prime is 1561418017. The next prime is 1561418041. The reversal of 1561418040 is 408141651.

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

It is a junction number, because it is equal to n+sod(n) for n = 1561417989 and 1561418007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561418041) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2412997 + ... + 2413643.

It is an arithmetic number, because the mean of its divisors is an integer number (16008840).

Almost surely, 2^1561418040 is an apocalyptic number.

1561418040 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 1561418040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3073697280).

1561418040 is an abundant number, since it is smaller than the sum of its proper divisors (4585976520).

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

1561418040 is a wasteful number, since it uses less digits than its factorization.

1561418040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 711 (or 694 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 1561418040 is about 39514.7825503317. The cubic root of 1561418040 is about 1160.1293058393.

Adding to 1561418040 its reverse (408141651), we get a palindrome (1969559691).

The spelling of 1561418040 in words is "one billion, five hundred sixty-one million, four hundred eighteen thousand, forty".