21970045 has 8 divisors (see below), whose sum is σ = 27076824. Its totient is φ = 17100864.

The previous prime is 21970043. The next prime is 21970051. The reversal of 21970045 is 54007912.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1800964 + 20169081 = 1342^2 + 4491^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21970045 - 2¹ = 21970043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21969995 and 21970022.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21970043) 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, 59194 + ... + 59563.

It is an arithmetic number, because the mean of its divisors is an integer number (3384603).

Almost surely, 2^21970045 is an apocalyptic number.

It is an amenable number.

21970045 is a deficient number, since it is larger than the sum of its proper divisors (5106779).

21970045 is a wasteful number, since it uses less digits than its factorization.

21970045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118799.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 21970045 is about 4687.2214583909. The cubic root of 21970045 is about 280.0767009260.

Adding to 21970045 its reverse (54007912), we get a palindrome (75977957).

The spelling of 21970045 in words is "twenty-one million, nine hundred seventy thousand, forty-five".