21051551395 has 32 divisors (see below), whose sum is σ = 29249372160. Its totient is φ = 14247098880.

The previous prime is 21051551387. The next prime is 21051551447. The reversal of 21051551395 is 59315515012.

It is not a de Polignac number, because 21051551395 - 2³ = 21051551387 is a prime.

It is a super-2 number, since 2×21051551395² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 934110 + ... + 956380.

It is an arithmetic number, because the mean of its divisors is an integer number (914042880).

Almost surely, 2^21051551395 is an apocalyptic number.

21051551395 is a deficient number, since it is larger than the sum of its proper divisors (8197820765).

21051551395 is a wasteful number, since it uses less digits than its factorization.

21051551395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22635.

The product of its (nonzero) digits is 33750, while the sum is 37.

The spelling of 21051551395 in words is "twenty-one billion, fifty-one million, five hundred fifty-one thousand, three hundred ninety-five".