134388821 has 6 divisors (see below), whose sum is σ = 156329910. Its totient is φ = 115190376.

The previous prime is 134388809. The next prime is 134388827. The reversal of 134388821 is 128883431.

It can be written as a sum of positive squares in only one way, i.e., 120780100 + 13608721 = 10990^2 + 3689^2 .

It is a de Polignac number, because none of the positive numbers 2^k-134388821 is a prime.

It is a super-3 number, since 3×134388821³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (134388827) 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, 1371266 + ... + 1371363.

It is an arithmetic number, because the mean of its divisors is an integer number (26054985).

Almost surely, 2^134388821 is an apocalyptic number.

It is an amenable number.

134388821 is a deficient number, since it is larger than the sum of its proper divisors (21941089).

134388821 is an equidigital number, since it uses as much as digits as its factorization.

134388821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2742643 (or 2742636 counting only the distinct ones).

The product of its digits is 36864, while the sum is 38.

The square root of 134388821 is about 11592.6192467449. The cubic root of 134388821 is about 512.2174636226.

It can be divided in two parts, 13 and 4388821, that added together give a palindrome (4388834).

The spelling of 134388821 in words is "one hundred thirty-four million, three hundred eighty-eight thousand, eight hundred twenty-one".