1559981 has 4 divisors (see below), whose sum is σ = 1570464. Its totient is φ = 1549500.

The previous prime is 1559969. The next prime is 1559983. The reversal of 1559981 is 1899551.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1899551 = 97 ⋅19583.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1559981 is a prime.

It is a super-2 number, since 2×1559981² = 4867081440722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1559983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5015 + ... + 5316.

It is an arithmetic number, because the mean of its divisors is an integer number (392616).

2^1559981 is an apocalyptic number.

It is an amenable number.

1559981 is a deficient number, since it is larger than the sum of its proper divisors (10483).

1559981 is a wasteful number, since it uses less digits than its factorization.

1559981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10482.

The product of its digits is 16200, while the sum is 38.

The square root of 1559981 is about 1248.9919935692. The cubic root of 1559981 is about 115.9773291010.

The spelling of 1559981 in words is "one million, five hundred fifty-nine thousand, nine hundred eighty-one".