16621692407 has 4 divisors (see below), whose sum is σ = 16625336496. Its totient is φ = 16618048320.

The previous prime is 16621692401. The next prime is 16621692413. The reversal of 16621692407 is 70429612661.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (16621692401) and next prime (16621692413).

It is a cyclic number.

It is not a de Polignac number, because 16621692407 - 2⁶ = 16621692343 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 (16621692401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1815194 + ... + 1824327.

It is an arithmetic number, because the mean of its divisors is an integer number (4156334124).

Almost surely, 2^16621692407 is an apocalyptic number.

16621692407 is a deficient number, since it is larger than the sum of its proper divisors (3644089).

16621692407 is an equidigital number, since it uses as much as digits as its factorization.

16621692407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3644088.

The product of its (nonzero) digits is 217728, while the sum is 44.

The spelling of 16621692407 in words is "sixteen billion, six hundred twenty-one million, six hundred ninety-two thousand, four hundred seven".