21980735 has 8 divisors (see below), whose sum is σ = 30145056. Its totient is φ = 15072480.

The previous prime is 21980719. The next prime is 21980771. The reversal of 21980735 is 53708912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21980735 - 2⁴ = 21980719 is a prime.

It is a super-2 number, since 2×21980735² = 966305422280450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35), and also a Moran number because the ratio is a prime number: 628021 = 21980735 / (2 + 1 + 9 + 8 + 0 + 7 + 3 + 5).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21980695 and 21980704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 313976 + ... + 314045.

It is an arithmetic number, because the mean of its divisors is an integer number (3768132).

Almost surely, 2^21980735 is an apocalyptic number.

21980735 is a deficient number, since it is larger than the sum of its proper divisors (8164321).

21980735 is an equidigital number, since it uses as much as digits as its factorization.

21980735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 628033.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 21980735 is about 4688.3616541389. The cubic root of 21980735 is about 280.1221193501.

The spelling of 21980735 in words is "twenty-one million, nine hundred eighty thousand, seven hundred thirty-five".