21514155 has 32 divisors (see below), whose sum is σ = 38277120. Its totient is φ = 10247040.

The previous prime is 21514153. The next prime is 21514159. The reversal of 21514155 is 55141512.

It is not a de Polignac number, because 21514155 - 2¹ = 21514153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21514153) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4266 + ... + 7824.

It is an arithmetic number, because the mean of its divisors is an integer number (1196160).

Almost surely, 2^21514155 is an apocalyptic number.

21514155 is a deficient number, since it is larger than the sum of its proper divisors (16762965).

21514155 is a wasteful number, since it uses less digits than its factorization.

21514155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3611.

The product of its digits is 1000, while the sum is 24.

The square root of 21514155 is about 4638.3353695049. The cubic root of 21514155 is about 278.1258983264.

Adding to 21514155 its reverse (55141512), we get a palindrome (76655667).

The spelling of 21514155 in words is "twenty-one million, five hundred fourteen thousand, one hundred fifty-five".