1979131969 has 4 divisors (see below), whose sum is σ = 1980396544. Its totient is φ = 1977867396.

The previous prime is 1979131967. The next prime is 1979131997. The reversal of 1979131969 is 9691319791.

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: 9691319791 = 643 ⋅15072037.

It is a cyclic number.

It is not a de Polignac number, because 1979131969 - 2¹ = 1979131967 is a prime.

It is a super-2 number, since 2×1979131969² = 7833926701435633922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1979131967) 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, 629937 + ... + 633070.

It is an arithmetic number, because the mean of its divisors is an integer number (495099136).

Almost surely, 2^1979131969 is an apocalyptic number.

It is an amenable number.

1979131969 is a deficient number, since it is larger than the sum of its proper divisors (1264575).

1979131969 is a wasteful number, since it uses less digits than its factorization.

1979131969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1264574.

The product of its digits is 826686, while the sum is 55.

The square root of 1979131969 is about 44487.4360803137. The cubic root of 1979131969 is about 1255.5237083492.

The spelling of 1979131969 in words is "one billion, nine hundred seventy-nine million, one hundred thirty-one thousand, nine hundred sixty-nine".