21051325651 has 8 divisors (see below), whose sum is σ = 21746340864. Its totient is φ = 20357306760.

The previous prime is 21051325597. The next prime is 21051325657. The reversal of 21051325651 is 15652315012.

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 21051325651 - 2²³ = 21042937043 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21051325657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 206005 + ... + 290758.

It is an arithmetic number, because the mean of its divisors is an integer number (2718292608).

Almost surely, 2^21051325651 is an apocalyptic number.

21051325651 is a deficient number, since it is larger than the sum of its proper divisors (695015213).

21051325651 is a wasteful number, since it uses less digits than its factorization.

21051325651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498161.

The product of its (nonzero) digits is 9000, while the sum is 31.

The spelling of 21051325651 in words is "twenty-one billion, fifty-one million, three hundred twenty-five thousand, six hundred fifty-one".