21802797 has 8 divisors (see below), whose sum is σ = 32300480. Its totient is φ = 14535180.

The previous prime is 21802793. The next prime is 21802811. The reversal of 21802797 is 79720812.

It is not a de Polignac number, because 21802797 - 2² = 21802793 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21802793) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 403729 + ... + 403782.

It is an arithmetic number, because the mean of its divisors is an integer number (4037560).

Almost surely, 2^21802797 is an apocalyptic number.

21802797 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21802797 is a deficient number, since it is larger than the sum of its proper divisors (10497683).

21802797 is an equidigital number, since it uses as much as digits as its factorization.

21802797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 807520 (or 807514 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 21802797 is about 4669.3465281557. The cubic root of 21802797 is about 279.3641908344.

The spelling of 21802797 in words is "twenty-one million, eight hundred two thousand, seven hundred ninety-seven".