1979420820 has 192 divisors, whose sum is σ = 6196974336. Its totient is φ = 468910080.

The previous prime is 1979420809. The next prime is 1979420831. The reversal of 1979420820 is 280249791.

It is an interprime number because it is at equal distance from previous prime (1979420809) and next prime (1979420831).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3087700 + ... + 3088340.

It is an arithmetic number, because the mean of its divisors is an integer number (32275908).

Almost surely, 2^1979420820 is an apocalyptic number.

1979420820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1979420820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3098487168).

1979420820 is an abundant number, since it is smaller than the sum of its proper divisors (4217553516).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1979420820 is a wasteful number, since it uses less digits than its factorization.

1979420820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810 (or 808 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 1979420820 is about 44490.6823953061. The cubic root of 1979420820 is about 1255.5847859062.

The spelling of 1979420820 in words is "one billion, nine hundred seventy-nine million, four hundred twenty thousand, eight hundred twenty".