21770544 has 20 divisors (see below), whose sum is σ = 56240696. Its totient is φ = 7256832.

The previous prime is 21770543. The next prime is 21770579. The reversal of 21770544 is 44507712.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21770543) 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, 226729 + ... + 226824.

Almost surely, 2^21770544 is an apocalyptic number.

21770544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21770544 is an abundant number, since it is smaller than the sum of its proper divisors (34470152).

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

21770544 is a wasteful number, since it uses less digits than its factorization.

21770544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453564 (or 453558 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 30.

The square root of 21770544 is about 4665.8915546763. The cubic root of 21770544 is about 279.2263678460.

The spelling of 21770544 in words is "twenty-one million, seven hundred seventy thousand, five hundred forty-four".