142221857 has 4 divisors (see below), whose sum is σ = 148405440. Its totient is φ = 136038276.

The previous prime is 142221823. The next prime is 142221869. The reversal of 142221857 is 758122241.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 758122241 = 1787 ⋅424243.

It is a cyclic number.

It is not a de Polignac number, because 142221857 - 2²⁰ = 141173281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (142221817) 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, 3091757 + ... + 3091802.

It is an arithmetic number, because the mean of its divisors is an integer number (37101360).

Almost surely, 2^142221857 is an apocalyptic number.

It is an amenable number.

142221857 is a deficient number, since it is larger than the sum of its proper divisors (6183583).

142221857 is an equidigital number, since it uses as much as digits as its factorization.

142221857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6183582.

The product of its digits is 8960, while the sum is 32.

The square root of 142221857 is about 11925.6805675819. The cubic root of 142221857 is about 521.9819053440.

The spelling of 142221857 in words is "one hundred forty-two million, two hundred twenty-one thousand, eight hundred fifty-seven".