29878381 has 16 divisors (see below), whose sum is σ = 34115760. Its totient is φ = 25966080.

The previous prime is 29878319. The next prime is 29878391. The reversal of 29878381 is 18387892.

It can be written as a sum of positive squares in 8 ways, for example, as 3960100 + 25918281 = 1990^2 + 5091^2 .

It is a 5-Lehmer number, since φ(29878381) divides (29878381-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 29878381 - 2⁷ = 29878253 is a prime.

It is a super-2 number, since 2×29878381² = 1785435302362322, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a deceptive number, since it divides R_29878380.

It is a Duffinian number.

Its product of digits (193536) is a multiple of the sum of its prime divisors (2016).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (29878301) 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, 14491 + ... + 16423.

It is an arithmetic number, because the mean of its divisors is an integer number (2132235).

It is a Poulet number, since it divides 2^29878380-1.

Almost surely, 2^29878381 is an apocalyptic number.

It is an amenable number.

29878381 is a deficient number, since it is larger than the sum of its proper divisors (4237379).

29878381 is a wasteful number, since it uses less digits than its factorization.

29878381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2016.

The product of its digits is 193536, while the sum is 46.

The square root of 29878381 is about 5466.1120551997. The cubic root of 29878381 is about 310.3027946776.

The spelling of 29878381 in words is "twenty-nine million, eight hundred seventy-eight thousand, three hundred eighty-one".