21770136 has 48 divisors (see below), whose sum is σ = 59281560. Its totient is φ = 7217280.

The previous prime is 21770129. The next prime is 21770141. The reversal of 21770136 is 63107712.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14476 + ... + 15908.

Almost surely, 2^21770136 is an apocalyptic number.

It is an amenable number.

21770136 is an abundant number, since it is smaller than the sum of its proper divisors (37511424).

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

21770136 is a wasteful number, since it uses less digits than its factorization.

21770136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1656 (or 1649 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 21770136 is about 4665.8478329238. The cubic root of 21770136 is about 279.2246235156.

Adding to 21770136 its reverse (63107712), we get a palindrome (84877848).

The spelling of 21770136 in words is "twenty-one million, seven hundred seventy thousand, one hundred thirty-six".