21986051 has 8 divisors (see below), whose sum is σ = 22274784. Its totient is φ = 21699520.

The previous prime is 21986023. The next prime is 21986057. The reversal of 21986051 is 15068912.

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

It is a cyclic number.

It is not a de Polignac number, because 21986051 - 2¹⁰ = 21985027 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21985999 and 21986017.

It is not an unprimeable number, because it can be changed into a prime (21986057) 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, 28511 + ... + 29271.

It is an arithmetic number, because the mean of its divisors is an integer number (2784348).

Almost surely, 2^21986051 is an apocalyptic number.

21986051 is a deficient number, since it is larger than the sum of its proper divisors (288733).

21986051 is a wasteful number, since it uses less digits than its factorization.

21986051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1101.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 21986051 is about 4688.9285556511. The cubic root of 21986051 is about 280.1446998682.

The spelling of 21986051 in words is "twenty-one million, nine hundred eighty-six thousand, fifty-one".