21054737 has 4 divisors (see below), whose sum is σ = 22968816. Its totient is φ = 19140660.

The previous prime is 21054703. The next prime is 21054757. The reversal of 21054737 is 73745012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21054737 - 2¹⁰ = 21053713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21054757) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 957023 + ... + 957044.

It is an arithmetic number, because the mean of its divisors is an integer number (5742204).

Almost surely, 2^21054737 is an apocalyptic number.

It is an amenable number.

21054737 is a deficient number, since it is larger than the sum of its proper divisors (1914079).

21054737 is a wasteful number, since it uses less digits than its factorization.

21054737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1914078.

The product of its (nonzero) digits is 5880, while the sum is 29.

The square root of 21054737 is about 4588.5441046153. The cubic root of 21054737 is about 276.1319163906.

Adding to 21054737 its reverse (73745012), we get a palindrome (94799749).

The spelling of 21054737 in words is "twenty-one million, fifty-four thousand, seven hundred thirty-seven".