21508151601 has 8 divisors (see below), whose sum is σ = 30186879520. Its totient is φ = 13584095712.

The previous prime is 21508151551. The next prime is 21508151617. The reversal of 21508151601 is 10615180512.

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

It is not a de Polignac number, because 21508151601 - 2⁷ = 21508151473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21508151671) 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, 188667940 + ... + 188668053.

It is an arithmetic number, because the mean of its divisors is an integer number (3773359940).

Almost surely, 2^21508151601 is an apocalyptic number.

It is an amenable number.

21508151601 is a deficient number, since it is larger than the sum of its proper divisors (8678727919).

21508151601 is a wasteful number, since it uses less digits than its factorization.

21508151601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377336015.

The product of its (nonzero) digits is 2400, while the sum is 30.

The spelling of 21508151601 in words is "twenty-one billion, five hundred eight million, one hundred fifty-one thousand, six hundred one".