21167001 has 12 divisors (see below), whose sum is σ = 31707312. Its totient is φ = 14111172.

The previous prime is 21166993. The next prime is 21167009. The reversal of 21167001 is 10076112.

It is an interprime number because it is at equal distance from previous prime (21166993) and next prime (21167009).

It is not a de Polignac number, because 21167001 - 2³ = 21166993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21167009) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43311 + ... + 43796.

It is an arithmetic number, because the mean of its divisors is an integer number (2642276).

Almost surely, 2^21167001 is an apocalyptic number.

It is an amenable number.

21167001 is a deficient number, since it is larger than the sum of its proper divisors (10540311).

21167001 is an frugal number, since it uses more digits than its factorization.

21167001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87122 (or 87110 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

The square root of 21167001 is about 4600.7609153269. The cubic root of 21167001 is about 276.6218257677.

The spelling of 21167001 in words is "twenty-one million, one hundred sixty-seven thousand, one".