20219002821 has 6 divisors (see below), whose sum is σ = 29205226310. Its totient is φ = 13479335208.

The previous prime is 20219002813. The next prime is 20219002873. The reversal of 20219002821 is 12820091202.

It can be written as a sum of positive squares in only one way, i.e., 14211977796 + 6007025025 = 119214^2 + 77505^2 .

It is not a de Polignac number, because 20219002821 - 2³ = 20219002813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20219000821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1123277926 + ... + 1123277943.

Almost surely, 2^20219002821 is an apocalyptic number.

It is an amenable number.

20219002821 is a deficient number, since it is larger than the sum of its proper divisors (8986223489).

20219002821 is a wasteful number, since it uses less digits than its factorization.

20219002821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2246555875 (or 2246555872 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The spelling of 20219002821 in words is "twenty billion, two hundred nineteen million, two thousand, eight hundred twenty-one".