1021738265640 has 384 divisors, whose sum is σ = 3620988502560. Its totient is φ = 248816074752.

The previous prime is 1021738265609. The next prime is 1021738265689. The reversal of 1021738265640 is 465628371201.

1021738265640 is a `hidden beast` number, since 1 + 0 + 2 + 1 + 7 + 3 + 82 + 6 + 564 + 0 = 666.

It can be written as a sum of positive squares in 16 ways, for example, as 162197896644 + 859540368996 = 402738^2 + 927114^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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 95 ways as a sum of consecutive naturals, for example, 84456072 + ... + 84468168.

Almost surely, 2^{1021738265640} is an apocalyptic number.

1021738265640 is a gapful number since it is divisible by the number (10) 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 1021738265640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1810494251280).

1021738265640 is an abundant number, since it is smaller than the sum of its proper divisors (2599250236920).

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

1021738265640 is a wasteful number, since it uses less digits than its factorization.

1021738265640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12541 (or 12534 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 1021738265640 in words is "one trillion, twenty-one billion, seven hundred thirty-eight million, two hundred sixty-five thousand, six hundred forty".