21554746 has 4 divisors (see below), whose sum is σ = 32332122. Its totient is φ = 10777372.

The previous prime is 21554737. The next prime is 21554773. The reversal of 21554746 is 64745512.

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

It can be written as a sum of positive squares in only one way, i.e., 13653025 + 7901721 = 3695^2 + 2811^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5388685 + ... + 5388688.

Almost surely, 2^21554746 is an apocalyptic number.

21554746 is a deficient number, since it is larger than the sum of its proper divisors (10777376).

21554746 is a wasteful number, since it uses less digits than its factorization.

21554746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10777375.

The product of its digits is 33600, while the sum is 34.

The square root of 21554746 is about 4642.7089075237. The cubic root of 21554746 is about 278.3007028651.

The spelling of 21554746 in words is "twenty-one million, five hundred fifty-four thousand, seven hundred forty-six".