21500157362551 has 16 divisors (see below), whose sum is σ = 25307195298624. Its totient is φ = 17879838096384.

The previous prime is 21500157362549. The next prime is 21500157362569. The reversal of 21500157362551 is 15526375100512.

It is a cyclic number.

It is not a de Polignac number, because 21500157362551 - 2¹ = 21500157362549 is a prime.

It is a super-2 number, since 2×21500157362551² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21500157362498 and 21500157362507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21500157362591) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117489580 + ... + 117672433.

It is an arithmetic number, because the mean of its divisors is an integer number (1581699706164).

Almost surely, 2^{21500157362551} is an apocalyptic number.

21500157362551 is a deficient number, since it is larger than the sum of its proper divisors (3807037936073).

21500157362551 is a wasteful number, since it uses less digits than its factorization.

21500157362551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235162410.

The product of its (nonzero) digits is 315000, while the sum is 43.

The spelling of 21500157362551 in words is "twenty-one trillion, five hundred billion, one hundred fifty-seven million, three hundred sixty-two thousand, five hundred fifty-one".