21345774 has 16 divisors (see below), whose sum is σ = 43206912. Its totient is φ = 7029368.

The previous prime is 21345767. The next prime is 21345809. The reversal of 21345774 is 47754312.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20934 + ... + 21929.

It is an arithmetic number, because the mean of its divisors is an integer number (2700432).

Almost surely, 2^21345774 is an apocalyptic number.

21345774 is an abundant number, since it is smaller than the sum of its proper divisors (21861138).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21345774 is a wasteful number, since it uses less digits than its factorization.

21345774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42951.

The product of its digits is 23520, while the sum is 33.

The square root of 21345774 is about 4620.1486989057. The cubic root of 21345774 is about 277.3984109921.

It can be divided in two parts, 213457 and 74, that added together give a triangular number (213531 = T₆₅₃).

The spelling of 21345774 in words is "twenty-one million, three hundred forty-five thousand, seven hundred seventy-four".