142778431 has 4 divisors (see below), whose sum is σ = 142802352. Its totient is φ = 142754512.

The previous prime is 142778429. The next prime is 142778443. The reversal of 142778431 is 134877241.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 134877241 = 83 ⋅1625027.

It is a cyclic number.

It is not a de Polignac number, because 142778431 - 2¹ = 142778429 is a prime.

It is a super-2 number, since 2×142778431² = 40771360717643522, 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 (142778401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5211 + ... + 17683.

It is an arithmetic number, because the mean of its divisors is an integer number (35700588).

Almost surely, 2^142778431 is an apocalyptic number.

142778431 is a deficient number, since it is larger than the sum of its proper divisors (23921).

142778431 is a wasteful number, since it uses less digits than its factorization.

142778431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23920.

The product of its digits is 37632, while the sum is 37.

The square root of 142778431 is about 11948.9928864319. The cubic root of 142778431 is about 522.6619306865.

The spelling of 142778431 in words is "one hundred forty-two million, seven hundred seventy-eight thousand, four hundred thirty-one".