284721993 has 16 divisors (see below), whose sum is σ = 433212160. Its totient is φ = 184683888.

The previous prime is 284721893. The next prime is 284722003. The reversal of 284721993 is 399127482.

It is not a de Polignac number, because 284721993 - 2¹³ = 284713801 is a prime.

It is a super-2 number, since 2×284721993² = 162133226595784098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (284721893) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141505 + ... + 143502.

It is an arithmetic number, because the mean of its divisors is an integer number (27075760).

Almost surely, 2^284721993 is an apocalyptic number.

It is an amenable number.

284721993 is a deficient number, since it is larger than the sum of its proper divisors (148490167).

284721993 is a wasteful number, since it uses less digits than its factorization.

284721993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285053 (or 285047 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 284721993 is about 16873.7071504753. The cubic root of 284721993 is about 657.8703878693.

The spelling of 284721993 in words is "two hundred eighty-four million, seven hundred twenty-one thousand, nine hundred ninety-three".