21996507 has 8 divisors (see below), whose sum is σ = 31584784. Its totient is φ = 13536288.

The previous prime is 21996503. The next prime is 21996551. The reversal of 21996507 is 70569912.

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

It is not a de Polignac number, because 21996507 - 2² = 21996503 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 564013 = 21996507 / (2 + 1 + 9 + 9 + 6 + 5 + 0 + 7).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21996503) 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, 281968 + ... + 282045.

It is an arithmetic number, because the mean of its divisors is an integer number (3948098).

Almost surely, 2^21996507 is an apocalyptic number.

21996507 is a deficient number, since it is larger than the sum of its proper divisors (9588277).

21996507 is a wasteful number, since it uses less digits than its factorization.

21996507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 564029.

The product of its (nonzero) digits is 34020, while the sum is 39.

The square root of 21996507 is about 4690.0433899912. The cubic root of 21996507 is about 280.1891026997.

The spelling of 21996507 in words is "twenty-one million, nine hundred ninety-six thousand, five hundred seven".