1021801517842 has 64 divisors (see below), whose sum is σ = 1826908473600. Its totient is φ = 419364046080.

The previous prime is 1021801517839. The next prime is 1021801517851. The reversal of 1021801517842 is 2487151081201.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1021801517795 and 1021801517804.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25079784 + ... + 25120492.

It is an arithmetic number, because the mean of its divisors is an integer number (28545444900).

Almost surely, 2^{1021801517842} is an apocalyptic number.

1021801517842 is a deficient number, since it is larger than the sum of its proper divisors (805106955758).

1021801517842 is a wasteful number, since it uses less digits than its factorization.

1021801517842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41251.

The product of its (nonzero) digits is 35840, while the sum is 40.

The spelling of 1021801517842 in words is "one trillion, twenty-one billion, eight hundred one million, five hundred seventeen thousand, eight hundred forty-two".