21142064 has 10 divisors (see below), whose sum is σ = 40962780. Its totient is φ = 10571024.

The previous prime is 21142061. The next prime is 21142087. The reversal of 21142064 is 46024112.

It is not an unprimeable number, because it can be changed into a prime (21142061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660674 + ... + 660705.

It is an arithmetic number, because the mean of its divisors is an integer number (4096278).

Almost surely, 2^21142064 is an apocalyptic number.

It is an amenable number.

21142064 is a deficient number, since it is larger than the sum of its proper divisors (19820716).

21142064 is a wasteful number, since it uses less digits than its factorization.

21142064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1321387 (or 1321381 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 21142064 is about 4598.0500214765. The cubic root of 21142064 is about 276.5131530094.

Adding to 21142064 its reverse (46024112), we get a palindrome (67166176).

The spelling of 21142064 in words is "twenty-one million, one hundred forty-two thousand, sixty-four".