21085157501 has 8 divisors (see below), whose sum is σ = 21976641024. Its totient is φ = 20206881360.

The previous prime is 21085157497. The next prime is 21085157537. The reversal of 21085157501 is 10575158012.

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

It is a cyclic number.

It is not a de Polignac number, because 21085157501 - 2² = 21085157497 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21085150501) 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, 3298586 + ... + 3304971.

It is an arithmetic number, because the mean of its divisors is an integer number (2747080128).

Almost surely, 2^21085157501 is an apocalyptic number.

It is an amenable number.

21085157501 is a deficient number, since it is larger than the sum of its proper divisors (891483523).

21085157501 is a wasteful number, since it uses less digits than its factorization.

21085157501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6603691.

The product of its (nonzero) digits is 14000, while the sum is 35.

The spelling of 21085157501 in words is "twenty-one billion, eighty-five million, one hundred fifty-seven thousand, five hundred one".