5111981 has 4 divisors (see below), whose sum is σ = 5842272. Its totient is φ = 4381692.

The previous prime is 5111963. The next prime is 5111999. The reversal of 5111981 is 1891115.

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: 1891115 = 5 ⋅378223.

It is an interprime number because it is at equal distance from previous prime (5111963) and next prime (5111999).

It is not a de Polignac number, because 5111981 - 2¹⁰ = 5110957 is a prime.

It is a super-2 number, since 2×5111981² = 52264699488722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 5111981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5111941) 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, 365135 + ... + 365148.

It is an arithmetic number, because the mean of its divisors is an integer number (1460568).

Almost surely, 2^5111981 is an apocalyptic number.

It is an amenable number.

5111981 is a deficient number, since it is larger than the sum of its proper divisors (730291).

5111981 is an equidigital number, since it uses as much as digits as its factorization.

5111981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 730290.

The product of its digits is 360, while the sum is 26.

The square root of 5111981 is about 2260.9690400357. The cubic root of 5111981 is about 172.2647468737.

The spelling of 5111981 in words is "five million, one hundred eleven thousand, nine hundred eighty-one".