1969581 has 4 divisors (see below), whose sum is σ = 2626112. Its totient is φ = 1313052.

The previous prime is 1969573. The next prime is 1969589. The reversal of 1969581 is 1859691.

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: 1859691 = 3 ⋅619897.

It is an interprime number because it is at equal distance from previous prime (1969573) and next prime (1969589).

It is not a de Polignac number, because 1969581 - 2³ = 1969573 is a prime.

It is a super-2 number, since 2×1969581² = 7758498631122, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

1969581 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1969589) 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, 328261 + ... + 328266.

It is an arithmetic number, because the mean of its divisors is an integer number (656528).

2^1969581 is an apocalyptic number.

It is an amenable number.

1969581 is a deficient number, since it is larger than the sum of its proper divisors (656531).

1969581 is an equidigital number, since it uses as much as digits as its factorization.

1969581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656530.

The product of its digits is 19440, while the sum is 39.

The square root of 1969581 is about 1403.4176142546. The cubic root of 1969581 is about 125.3500799702.

The spelling of 1969581 in words is "one million, nine hundred sixty-nine thousand, five hundred eighty-one".