921753728028 has 144 divisors (see below), whose sum is σ = 2780337399840. Its totient is φ = 263316033792.

The previous prime is 921753728017. The next prime is 921753728047. The reversal of 921753728028 is 820827357129.

921753728028 is a `hidden beast` number, since 9 + 2 + 1 + 7 + 537 + 2 + 80 + 28 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 49931376 + ... + 49949832.

It is an arithmetic number, because the mean of its divisors is an integer number (19307898610).

Almost surely, 2^921753728028 is an apocalyptic number.

921753728028 is a gapful number since it is divisible by the number (98) 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 921753728028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1390168699920).

921753728028 is an abundant number, since it is smaller than the sum of its proper divisors (1858583671812).

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

921753728028 is a wasteful number, since it uses less digits than its factorization.

921753728028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27921 (or 27906 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 54.

The spelling of 921753728028 in words is "nine hundred twenty-one billion, seven hundred fifty-three million, seven hundred twenty-eight thousand, twenty-eight".