1021642857145 has 4 divisors (see below), whose sum is σ = 1225971428580. Its totient is φ = 817314285712.

The previous prime is 1021642857127. The next prime is 1021642857187. The reversal of 1021642857145 is 5417582461201.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 637153571961 + 384489285184 = 798219^2 + 620072^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021642857145 - 2¹⁷ = 1021642726073 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1021642857095 and 1021642857104.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102164285710 + ... + 102164285719.

It is an arithmetic number, because the mean of its divisors is an integer number (306492857145).

Almost surely, 2^{1021642857145} is an apocalyptic number.

It is an amenable number.

1021642857145 is a deficient number, since it is larger than the sum of its proper divisors (204328571435).

1021642857145 is an equidigital number, since it uses as much as digits as its factorization.

1021642857145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204328571434.

The product of its (nonzero) digits is 537600, while the sum is 46.

The spelling of 1021642857145 in words is "one trillion, twenty-one billion, six hundred forty-two million, eight hundred fifty-seven thousand, one hundred forty-five".