21542467 has 12 divisors (see below), whose sum is σ = 22743784. Its totient is φ = 20401920.

The previous prime is 21542459. The next prime is 21542483. The reversal of 21542467 is 76424512.

It is not a de Polignac number, because 21542467 - 2³ = 21542459 is a prime.

It is a super-3 number, since 3×21542467³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21542167) 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 11 ways as a sum of consecutive naturals, for example, 101992 + ... + 102202.

Almost surely, 2^21542467 is an apocalyptic number.

21542467 is a deficient number, since it is larger than the sum of its proper divisors (1201317).

21542467 is a wasteful number, since it uses less digits than its factorization.

21542467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450 (or 427 counting only the distinct ones).

The product of its digits is 13440, while the sum is 31.

The square root of 21542467 is about 4641.3863230720. The cubic root of 21542467 is about 278.2478467032.

Adding to 21542467 its reverse (76424512), we get a palindrome (97966979).

The spelling of 21542467 in words is "twenty-one million, five hundred forty-two thousand, four hundred sixty-seven".