21060999 has 8 divisors (see below), whose sum is σ = 31201520. Its totient is φ = 14040648.

The previous prime is 21060967. The next prime is 21061009. The reversal of 21060999 is 99906012.

It is not a de Polignac number, because 21060999 - 2⁵ = 21060967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21060929) 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, 389992 + ... + 390045.

It is an arithmetic number, because the mean of its divisors is an integer number (3900190).

Almost surely, 2^21060999 is an apocalyptic number.

21060999 is a deficient number, since it is larger than the sum of its proper divisors (10140521).

21060999 is an equidigital number, since it uses as much as digits as its factorization.

21060999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780046 (or 780040 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The square root of 21060999 is about 4589.2264053978. The cubic root of 21060999 is about 276.1592889586.

The spelling of 21060999 in words is "twenty-one million, sixty thousand, nine hundred ninety-nine".