20629664 has 48 divisors (see below), whose sum is σ = 44815680. Its totient is φ = 9269760.

The previous prime is 20629657. The next prime is 20629691. The reversal of 20629664 is 46692602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35972 + ... + 36540.

It is an arithmetic number, because the mean of its divisors is an integer number (933660).

Almost surely, 2^20629664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20629664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22407840).

20629664 is an abundant number, since it is smaller than the sum of its proper divisors (24186016).

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

20629664 is a wasteful number, since it uses less digits than its factorization.

20629664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693 (or 685 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 20629664 is about 4541.9889916203. The cubic root of 20629664 is about 274.2609976901.

It can be divided in two parts, 206 and 29664, that multiplied together give a square (6110784 = 2472²).

The spelling of 20629664 in words is "twenty million, six hundred twenty-nine thousand, six hundred sixty-four".