20142391 has 8 divisors (see below), whose sum is σ = 20478960. Its totient is φ = 19808448.

The previous prime is 20142389. The next prime is 20142401. The reversal of 20142391 is 19324102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20142391 - 2¹ = 20142389 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 (20142301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19705 + ... + 20701.

It is an arithmetic number, because the mean of its divisors is an integer number (2559870).

Almost surely, 2^20142391 is an apocalyptic number.

20142391 is a deficient number, since it is larger than the sum of its proper divisors (336569).

20142391 is an equidigital number, since it uses as much as digits as its factorization.

20142391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1313.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 20142391 is about 4488.0275177410. The cubic root of 20142391 is about 272.0844199826.

Adding to 20142391 its reverse (19324102), we get a palindrome (39466493).

The spelling of 20142391 in words is "twenty million, one hundred forty-two thousand, three hundred ninety-one".