21140706 has 16 divisors (see below), whose sum is σ = 42368544. Its totient is φ = 7032384.

The previous prime is 21140701. The next prime is 21140719. The reversal of 21140706 is 60704112.

It is not an unprimeable number, because it can be changed into a prime (21140701) 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, 231 + ... + 6506.

It is an arithmetic number, because the mean of its divisors is an integer number (2648034).

Almost surely, 2^21140706 is an apocalyptic number.

21140706 is an abundant number, since it is smaller than the sum of its proper divisors (21227838).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21140706 is a wasteful number, since it uses less digits than its factorization.

21140706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7265.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21140706 is about 4597.9023478104. The cubic root of 21140706 is about 276.5072325389.

Adding to 21140706 its reverse (60704112), we get a palindrome (81844818).

The spelling of 21140706 in words is "twenty-one million, one hundred forty thousand, seven hundred six".