21158007 has 16 divisors (see below), whose sum is σ = 30655968. Its totient is φ = 12902400.

The previous prime is 21158003. The next prime is 21158041. The reversal of 21158007 is 70085112.

It is not a de Polignac number, because 21158007 - 2² = 21158003 is a prime.

It is a super-2 number, since 2×21158007² = 895322520424098, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21158003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2007 + ... + 6807.

It is an arithmetic number, because the mean of its divisors is an integer number (1915998).

Almost surely, 2^21158007 is an apocalyptic number.

21158007 is a deficient number, since it is larger than the sum of its proper divisors (9497961).

21158007 is a wasteful number, since it uses less digits than its factorization.

21158007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4930.

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 21158007 is about 4599.7833644640. The cubic root of 21158007 is about 276.5826407305.

The spelling of 21158007 in words is "twenty-one million, one hundred fifty-eight thousand, seven".