21436942 has 8 divisors (see below), whose sum is σ = 32700600. Its totient is φ = 10536744.

The previous prime is 21436939. The next prime is 21436951. The reversal of 21436942 is 24963412.

It is a happy number.

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

It is a super-2 number, since 2×21436942² = 919084964622728, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 90717 + ... + 90952.

It is an arithmetic number, because the mean of its divisors is an integer number (4087575).

Almost surely, 2^21436942 is an apocalyptic number.

21436942 is a deficient number, since it is larger than the sum of its proper divisors (11263658).

21436942 is a wasteful number, since it uses less digits than its factorization.

21436942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181730.

The product of its digits is 10368, while the sum is 31.

The square root of 21436942 is about 4630.0045356349. The cubic root of 21436942 is about 277.7927738156.

The spelling of 21436942 in words is "twenty-one million, four hundred thirty-six thousand, nine hundred forty-two".