81222955 has 32 divisors (see below), whose sum is σ = 110315520. Its totient is φ = 56891520.

The previous prime is 81222949. The next prime is 81222979. The reversal of 81222955 is 55922218.

81222955 = 228² + 229² + ... + 634².

It is a happy number.

It is not a de Polignac number, because 81222955 - 2⁹ = 81222443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81222955.

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, 339726 + ... + 339964.

It is an arithmetic number, because the mean of its divisors is an integer number (3447360).

Almost surely, 2^81222955 is an apocalyptic number.

81222955 is a deficient number, since it is larger than the sum of its proper divisors (29092565).

81222955 is a wasteful number, since it uses less digits than its factorization.

81222955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459.

The product of its digits is 14400, while the sum is 34.

The square root of 81222955 is about 9012.3778771199. The cubic root of 81222955 is about 433.0714910572.

The spelling of 81222955 in words is "eighty-one million, two hundred twenty-two thousand, nine hundred fifty-five".