997793621390 has 16 divisors (see below), whose sum is σ = 1839834092880. Its totient is φ = 389382876480.

The previous prime is 997793621387. The next prime is 997793621399. The reversal of 997793621390 is 93126397799.

It is a super-2 number, since 2×997793621390² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997793621399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1216821080 + ... + 1216821899.

It is an arithmetic number, because the mean of its divisors is an integer number (114989630805).

Almost surely, 2^997793621390 is an apocalyptic number.

997793621390 is a deficient number, since it is larger than the sum of its proper divisors (842040471490).

997793621390 is a wasteful number, since it uses less digits than its factorization.

997793621390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2433643027.

The product of its (nonzero) digits is 34720812, while the sum is 65.

The spelling of 997793621390 in words is "nine hundred ninety-seven billion, seven hundred ninety-three million, six hundred twenty-one thousand, three hundred ninety".