1721977521264 has 2880 divisors, whose sum is σ = 7463039001600. Its totient is φ = 372471644160.

The previous prime is 1721977521241. The next prime is 1721977521301. The reversal of 1721977521264 is 4621257791271.

It is a happy number.

1721977521264 is a `hidden beast` number, since 1 + 7 + 2 + 1 + 97 + 7 + 521 + 26 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 1721977521264.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 23588733132 + ... + 23588733204.

Almost surely, 2^{1721977521264} is an apocalyptic number.

1721977521264 is a gapful number since it is divisible by the number (14) 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 1721977521264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3731519500800).

1721977521264 is an abundant number, since it is smaller than the sum of its proper divisors (5741061480336).

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

1721977521264 is a wasteful number, since it uses less digits than its factorization.

1721977521264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186 (or 157 counting only the distinct ones).

The product of its digits is 2963520, while the sum is 54.

The spelling of 1721977521264 in words is "one trillion, seven hundred twenty-one billion, nine hundred seventy-seven million, five hundred twenty-one thousand, two hundred sixty-four".