21967401 has 8 divisors (see below), whose sum is σ = 30831520. Its totient is φ = 13874112.

The previous prime is 21967397. The next prime is 21967403. The reversal of 21967401 is 10476912.

It is a happy number.

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

It is not a de Polignac number, because 21967401 - 2² = 21967397 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21967403) 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, 192640 + ... + 192753.

It is an arithmetic number, because the mean of its divisors is an integer number (3853940).

Almost surely, 2^21967401 is an apocalyptic number.

It is an amenable number.

21967401 is a deficient number, since it is larger than the sum of its proper divisors (8864119).

21967401 is a wasteful number, since it uses less digits than its factorization.

21967401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385415.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 21967401 is about 4686.9394064784. The cubic root of 21967401 is about 280.0654651350.

The spelling of 21967401 in words is "twenty-one million, nine hundred sixty-seven thousand, four hundred one".