1397771648 has 256 divisors, whose sum is σ = 3655680000. Its totient is φ = 528353280.

The previous prime is 1397771647. The next prime is 1397771657. The reversal of 1397771648 is 8461777931.

It is a self number, because there is not a number n which added to its sum of digits gives 1397771648.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1397771647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17693273 + ... + 17693351.

It is an arithmetic number, because the mean of its divisors is an integer number (14280000).

Almost surely, 2^1397771648 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 1397771648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1827840000).

1397771648 is an abundant number, since it is smaller than the sum of its proper divisors (2257908352).

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

1397771648 is an equidigital number, since it uses as much as digits as its factorization.

1397771648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158 (or 132 counting only the distinct ones).

The product of its digits is 1778112, while the sum is 53.

The square root of 1397771648 is about 37386.7844030481. The cubic root of 1397771648 is about 1118.0950952934.

The spelling of 1397771648 in words is "one billion, three hundred ninety-seven million, seven hundred seventy-one thousand, six hundred forty-eight".