21655702 has 4 divisors (see below), whose sum is σ = 32483556. Its totient is φ = 10827850.

The previous prime is 21655679. The next prime is 21655709. The reversal of 21655702 is 20755612.

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

It is a super-2 number, since 2×21655702² = 937938858225608, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21655709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5413924 + ... + 5413927.

It is an arithmetic number, because the mean of its divisors is an integer number (8120889).

Almost surely, 2^21655702 is an apocalyptic number.

21655702 is a deficient number, since it is larger than the sum of its proper divisors (10827854).

21655702 is a wasteful number, since it uses less digits than its factorization.

21655702 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10827853.

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 21655702 is about 4653.5687380762. The cubic root of 21655702 is about 278.7345187699.

The spelling of 21655702 in words is "twenty-one million, six hundred fifty-five thousand, seven hundred two".