221769738 has 80 divisors (see below), whose sum is σ = 514643976. Its totient is φ = 71331840.

The previous prime is 221769733. The next prime is 221769763. The reversal of 221769738 is 837967122.

221769738 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 157176369 + 64593369 = 12537^2 + 8037^2 .

It is a junction number, because it is equal to n+sod(n) for n = 221769693 and 221769702.

It is not an unprimeable number, because it can be changed into a prime (221769733) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1148970 + ... + 1149162.

Almost surely, 2^221769738 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221769738, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (257321988).

221769738 is an abundant number, since it is smaller than the sum of its proper divisors (292874238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221769738 is a wasteful number, since it uses less digits than its factorization.

221769738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421 (or 412 counting only the distinct ones).

The product of its digits is 254016, while the sum is 45.

The square root of 221769738 is about 14891.9353342673. The cubic root of 221769738 is about 605.2954757316.

The spelling of 221769738 in words is "two hundred twenty-one million, seven hundred sixty-nine thousand, seven hundred thirty-eight".