21961067 has 4 divisors (see below), whose sum is σ = 22915920. Its totient is φ = 21006216.

The previous prime is 21961061. The next prime is 21961073. The reversal of 21961067 is 76016912.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21961061) and next prime (21961073).

It is a cyclic number.

It is not a de Polignac number, because 21961067 - 2⁸ = 21960811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21961061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 477392 + ... + 477437.

It is an arithmetic number, because the mean of its divisors is an integer number (5728980).

Almost surely, 2^21961067 is an apocalyptic number.

21961067 is a deficient number, since it is larger than the sum of its proper divisors (954853).

21961067 is an equidigital number, since it uses as much as digits as its factorization.

21961067 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 954852.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 21961067 is about 4686.2636502869. The cubic root of 21961067 is about 280.0385448637.

Adding to 21961067 its reverse (76016912), we get a palindrome (97977979).

The spelling of 21961067 in words is "twenty-one million, nine hundred sixty-one thousand, sixty-seven".