1979651520 has 672 divisors, whose sum is σ = 8672901120. Its totient is φ = 402554880.

The previous prime is 1979651461. The next prime is 1979651521. The reversal of 1979651520 is 251569791.

1979651520 is a `hidden beast` number, since 1 + 9 + 79 + 6 + 51 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1979651521) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 17518984 + ... + 17519096.

Almost surely, 2^1979651520 is an apocalyptic number.

1979651520 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 1979651520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4336450560).

1979651520 is an abundant number, since it is smaller than the sum of its proper divisors (6693249600).

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

1979651520 is a wasteful number, since it uses less digits than its factorization.

1979651520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233 (or 220 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 45.

The square root of 1979651520 is about 44493.2749974645. The cubic root of 1979651520 is about 1255.6335631638.

The spelling of 1979651520 in words is "one billion, nine hundred seventy-nine million, six hundred fifty-one thousand, five hundred twenty".