162881821 has 4 divisors (see below), whose sum is σ = 162992412. Its totient is φ = 162771232.

The previous prime is 162881819. The next prime is 162881833. The reversal of 162881821 is 128188261.

It is a happy number.

162881821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 109956196 + 52925625 = 10486^2 + 7275^2 .

It is a cyclic number.

It is not a de Polignac number, because 162881821 - 2¹ = 162881819 is a prime.

It is a super-2 number, since 2×162881821² = 53060975224552082, which contains 22 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 (162881801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53056 + ... + 56041.

It is an arithmetic number, because the mean of its divisors is an integer number (40748103).

Almost surely, 2^162881821 is an apocalyptic number.

It is an amenable number.

162881821 is a deficient number, since it is larger than the sum of its proper divisors (110591).

162881821 is a wasteful number, since it uses less digits than its factorization.

162881821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110590.

The product of its digits is 12288, while the sum is 37.

The square root of 162881821 is about 12762.5162487654. The cubic root of 162881821 is about 546.1235089823.

The spelling of 162881821 in words is "one hundred sixty-two million, eight hundred eighty-one thousand, eight hundred twenty-one".