21902084 has 6 divisors (see below), whose sum is σ = 38328654. Its totient is φ = 10951040.

The previous prime is 21902063. The next prime is 21902087. The reversal of 21902084 is 48020912.

It can be written as a sum of positive squares in only one way, i.e., 20052484 + 1849600 = 4478^2 + 1360^2 .

It is not an unprimeable number, because it can be changed into a prime (21902087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2737757 + ... + 2737764.

It is an arithmetic number, because the mean of its divisors is an integer number (6388109).

Almost surely, 2^21902084 is an apocalyptic number.

It is an amenable number.

21902084 is a deficient number, since it is larger than the sum of its proper divisors (16426570).

21902084 is a wasteful number, since it uses less digits than its factorization.

21902084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5475525 (or 5475523 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 21902084 is about 4679.9662391945. The cubic root of 21902084 is about 279.7876110458.

Adding to 21902084 its reverse (48020912), we get a palindrome (69922996).

The spelling of 21902084 in words is "twenty-one million, nine hundred two thousand, eighty-four".