21620701650 has 48 divisors (see below), whose sum is σ = 53647798464. Its totient is φ = 5762460480.

The previous prime is 21620701631. The next prime is 21620701657. The reversal of 21620701650 is 5610702612.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21620701657) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 252667 + ... + 327233.

It is an arithmetic number, because the mean of its divisors is an integer number (1117662468).

Almost surely, 2^21620701650 is an apocalyptic number.

21620701650 is an abundant number, since it is smaller than the sum of its proper divisors (32027096814).

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

21620701650 is a wasteful number, since it uses less digits than its factorization.

21620701650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76515 (or 76510 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The spelling of 21620701650 in words is "twenty-one billion, six hundred twenty million, seven hundred one thousand, six hundred fifty".