21376545 has 16 divisors (see below), whose sum is σ = 35690112. Its totient is φ = 10904960.

The previous prime is 21376519. The next prime is 21376559. The reversal of 21376545 is 54567312.

It is not a de Polignac number, because 21376545 - 2¹⁰ = 21375521 is a prime.

It is a super-2 number, since 2×21376545² = 913913352274050, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30636 + ... + 31325.

It is an arithmetic number, because the mean of its divisors is an integer number (2230632).

Almost surely, 2^21376545 is an apocalyptic number.

It is an amenable number.

21376545 is a deficient number, since it is larger than the sum of its proper divisors (14313567).

21376545 is a wasteful number, since it uses less digits than its factorization.

21376545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61992.

The product of its digits is 25200, while the sum is 33.

The square root of 21376545 is about 4623.4775872713. The cubic root of 21376545 is about 277.5316415507.

The spelling of 21376545 in words is "twenty-one million, three hundred seventy-six thousand, five hundred forty-five".