21293774 has 4 divisors (see below), whose sum is σ = 31940664. Its totient is φ = 10646886.

The previous prime is 21293761. The next prime is 21293777. The reversal of 21293774 is 47739212.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×21293774² = 906849622326152, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21293777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5323442 + ... + 5323445.

It is an arithmetic number, because the mean of its divisors is an integer number (7985166).

Almost surely, 2^21293774 is an apocalyptic number.

21293774 is a deficient number, since it is larger than the sum of its proper divisors (10646890).

21293774 is a wasteful number, since it uses less digits than its factorization.

21293774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10646889.

The product of its digits is 21168, while the sum is 35.

The square root of 21293774 is about 4614.5177429500. The cubic root of 21293774 is about 277.1729729811.

The spelling of 21293774 in words is "twenty-one million, two hundred ninety-three thousand, seven hundred seventy-four".