21893151 has 12 divisors (see below), whose sum is σ = 33956952. Its totient is φ = 12510288.

The previous prime is 21893147. The next prime is 21893153. The reversal of 21893151 is 15139812.

It is not a de Polignac number, because 21893151 - 2² = 21893147 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21893153) 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, 74320 + ... + 74613.

It is an arithmetic number, because the mean of its divisors is an integer number (2829746).

Almost surely, 2^21893151 is an apocalyptic number.

21893151 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21893151 is a deficient number, since it is larger than the sum of its proper divisors (12063801).

21893151 is a wasteful number, since it uses less digits than its factorization.

21893151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148950 (or 148943 counting only the distinct ones).

The product of its digits is 2160, while the sum is 30.

The square root of 21893151 is about 4679.0117546337. The cubic root of 21893151 is about 279.7495677466.

The spelling of 21893151 in words is "twenty-one million, eight hundred ninety-three thousand, one hundred fifty-one".