21506074 has 8 divisors (see below), whose sum is σ = 32294880. Its totient is φ = 10741116.

The previous prime is 21506059. The next prime is 21506083. The reversal of 21506074 is 47060512.

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

It is a super-2 number, since 2×21506074² = 925022437786952, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3504 + ... + 7435.

It is an arithmetic number, because the mean of its divisors is an integer number (4036860).

Almost surely, 2^21506074 is an apocalyptic number.

21506074 is a deficient number, since it is larger than the sum of its proper divisors (10788806).

21506074 is a wasteful number, since it uses less digits than its factorization.

21506074 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11924.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 21506074 is about 4637.4641777592. The cubic root of 21506074 is about 278.0910713820.

Adding to 21506074 its reverse (47060512), we get a palindrome (68566586).

The spelling of 21506074 in words is "twenty-one million, five hundred six thousand, seventy-four".