997378077784 has 64 divisors (see below), whose sum is σ = 2063750400000. Its totient is φ = 448099787520.

The previous prime is 997378077769. The next prime is 997378077863. The reversal of 997378077784 is 487770873799.

It is a self number, because there is not a number n which added to its sum of digits gives 997378077784.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23466937 + ... + 23509399.

It is an arithmetic number, because the mean of its divisors is an integer number (32246100000).

Almost surely, 2^997378077784 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997378077784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1031875200000).

997378077784 is an abundant number, since it is smaller than the sum of its proper divisors (1066372322216).

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

997378077784 is a wasteful number, since it uses less digits than its factorization.

997378077784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45568 (or 45564 counting only the distinct ones).

The product of its (nonzero) digits is 1045529856, while the sum is 76.

The spelling of 997378077784 in words is "nine hundred ninety-seven billion, three hundred seventy-eight million, seventy-seven thousand, seven hundred eighty-four".