21970061 has 8 divisors (see below), whose sum is σ = 23173920. Its totient is φ = 20770992.

The previous prime is 21970051. The next prime is 21970063. The reversal of 21970061 is 16007912.

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 21970061 - 2¹⁴ = 21953677 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21970061.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21970063) 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, 12131 + ... + 13823.

It is an arithmetic number, because the mean of its divisors is an integer number (2896740).

Almost surely, 2^21970061 is an apocalyptic number.

It is an amenable number.

21970061 is a deficient number, since it is larger than the sum of its proper divisors (1203859).

21970061 is a wasteful number, since it uses less digits than its factorization.

21970061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2395.

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 21970061 is about 4687.2231651587. The cubic root of 21970061 is about 280.0767689160.

Adding to 21970061 its reverse (16007912), we get a palindrome (37977973).

The spelling of 21970061 in words is "twenty-one million, nine hundred seventy thousand, sixty-one".