21550210072 has 16 divisors (see below), whose sum is σ = 42783505560. Its totient is φ = 10141275264.

The previous prime is 21550210063. The next prime is 21550210081. The reversal of 21550210072 is 27001205512.

It is an interprime number because it is at equal distance from previous prime (21550210063) and next prime (21550210081).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79228578 + ... + 79228849.

Almost surely, 2^21550210072 is an apocalyptic number.

It is an amenable number.

21550210072 is a deficient number, since it is larger than the sum of its proper divisors (21233295488).

21550210072 is a wasteful number, since it uses less digits than its factorization.

21550210072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158457450 (or 158457446 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 25.

Adding to 21550210072 its reverse (27001205512), we get a palindrome (48551415584).

The spelling of 21550210072 in words is "twenty-one billion, five hundred fifty million, two hundred ten thousand, seventy-two".