1021865688044 has 6 divisors (see below), whose sum is σ = 1788264954084. Its totient is φ = 510932844020.

The previous prime is 1021865688023. The next prime is 1021865688071. The reversal of 1021865688044 is 4408865681201.

It is a super-4 number, since 4×1021865688044⁴ (a number of 49 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127733211002 + ... + 127733211009.

It is an arithmetic number, because the mean of its divisors is an integer number (298044159014).

Almost surely, 2^{1021865688044} is an apocalyptic number.

It is an amenable number.

1021865688044 is a deficient number, since it is larger than the sum of its proper divisors (766399266040).

1021865688044 is a wasteful number, since it uses less digits than its factorization.

1021865688044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255466422015 (or 255466422013 counting only the distinct ones).

The product of its (nonzero) digits is 2949120, while the sum is 53.

The spelling of 1021865688044 in words is "one trillion, twenty-one billion, eight hundred sixty-five million, six hundred eighty-eight thousand, forty-four".