1531989 has 36 divisors (see below), whose sum is σ = 2554240. Its totient is φ = 881280.

The previous prime is 1531987. The next prime is 1531991. The reversal of 1531989 is 9891351.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1531987) and next prime (1531991).

It is not a de Polignac number, because 1531989 - 2¹ = 1531987 is a prime.

It is a super-2 number, since 2×1531989² = 4693980592242, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

Its product of digits (9720) is a multiple of the sum of its prime factors (90).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1531987) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 49404 + ... + 49434.

2^1531989 is an apocalyptic number.

1531989 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1531989 is a deficient number, since it is larger than the sum of its proper divisors (1022251).

1531989 is a wasteful number, since it uses less digits than its factorization.

1531989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 70 counting only the distinct ones).

The product of its digits is 9720, while the sum is 36.

The square root of 1531989 is about 1237.7354321502. The cubic root of 1531989 is about 115.2794464278.

The spelling of 1531989 in words is "one million, five hundred thirty-one thousand, nine hundred eighty-nine".