221397903 has 6 divisors (see below), whose sum is σ = 319796984. Its totient is φ = 147598596.

The previous prime is 221397893. The next prime is 221397923. The reversal of 221397903 is 309793122.

221397903 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221397903 - 2¹³ = 221389711 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 (221397923) 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, 12299875 + ... + 12299892.

Almost surely, 2^221397903 is an apocalyptic number.

221397903 is a deficient number, since it is larger than the sum of its proper divisors (98399081).

221397903 is a wasteful number, since it uses less digits than its factorization.

221397903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24599773 (or 24599770 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 36.

The square root of 221397903 is about 14879.4456549967. The cubic root of 221397903 is about 604.9569925943.

The spelling of 221397903 in words is "two hundred twenty-one million, three hundred ninety-seven thousand, nine hundred three".