1521779035920 has 960 divisors, whose sum is σ = 5877374681088. Its totient is φ = 322403328000.

The previous prime is 1521779035879. The next prime is 1521779035927. The reversal of 1521779035920 is 295309771251.

It is a happy number.

It is a super-2 number, since 2×1521779035920² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1521779035927) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 650053950 + ... + 650056290.

Almost surely, 2^{1521779035920} is an apocalyptic number.

1521779035920 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 1521779035920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2938687340544).

1521779035920 is an abundant number, since it is smaller than the sum of its proper divisors (4355595645168).

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

1521779035920 is a wasteful number, since it uses less digits than its factorization.

1521779035920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2472 (or 2453 counting only the distinct ones).

The product of its (nonzero) digits is 1190700, while the sum is 51.

The spelling of 1521779035920 in words is "one trillion, five hundred twenty-one billion, seven hundred seventy-nine million, thirty-five thousand, nine hundred twenty".