21620319537 has 8 divisors (see below), whose sum is σ = 28840743904. Its totient is φ = 14406720768.

The previous prime is 21620319463. The next prime is 21620319541. The reversal of 21620319537 is 73591302612.

It is a happy number.

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

It is not a de Polignac number, because 21620319537 - 2¹⁴ = 21620303153 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21620319495 and 21620319504.

It is not an unprimeable number, because it can be changed into a prime (21620319737) 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, 1699003 + ... + 1711680.

It is an arithmetic number, because the mean of its divisors is an integer number (3605092988).

Almost surely, 2^21620319537 is an apocalyptic number.

It is an amenable number.

21620319537 is a deficient number, since it is larger than the sum of its proper divisors (7220424367).

21620319537 is a wasteful number, since it uses less digits than its factorization.

21620319537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3412799.

The product of its (nonzero) digits is 68040, while the sum is 39.

The spelling of 21620319537 in words is "twenty-one billion, six hundred twenty million, three hundred nineteen thousand, five hundred thirty-seven".