1421028817 has 4 divisors (see below), whose sum is σ = 1530338740. Its totient is φ = 1311718896.

The previous prime is 1421028787. The next prime is 1421028839. The reversal of 1421028817 is 7188201241.

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 215619856 + 1205408961 = 14684^2 + 34719^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1421028817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1421028887) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54654942 + ... + 54654967.

It is an arithmetic number, because the mean of its divisors is an integer number (382584685).

Almost surely, 2^1421028817 is an apocalyptic number.

It is an amenable number.

1421028817 is a deficient number, since it is larger than the sum of its proper divisors (109309923).

1421028817 is a wasteful number, since it uses less digits than its factorization.

1421028817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109309922.

The product of its (nonzero) digits is 7168, while the sum is 34.

The square root of 1421028817 is about 37696.5358753294. The cubic root of 1421028817 is about 1124.2622500012.

The spelling of 1421028817 in words is "one billion, four hundred twenty-one million, twenty-eight thousand, eight hundred seventeen".