21147142 has 8 divisors (see below), whose sum is σ = 32458536. Its totient is φ = 10327632.

The previous prime is 21147127. The next prime is 21147157. The reversal of 21147142 is 24174112.

It is an interprime number because it is at equal distance from previous prime (21147127) and next prime (21147157).

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

It is a super-2 number, since 2×21147142² = 894403229536328, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122863 + ... + 123034.

It is an arithmetic number, because the mean of its divisors is an integer number (4057317).

Almost surely, 2^21147142 is an apocalyptic number.

21147142 is a deficient number, since it is larger than the sum of its proper divisors (11311394).

21147142 is a wasteful number, since it uses less digits than its factorization.

21147142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245942.

The product of its digits is 448, while the sum is 22.

The square root of 21147142 is about 4598.6021789235. The cubic root of 21147142 is about 276.5352893122.

The spelling of 21147142 in words is "twenty-one million, one hundred forty-seven thousand, one hundred forty-two".