221151694949 has 4 divisors (see below), whose sum is σ = 221158463436. Its totient is φ = 221144926464.

The previous prime is 221151694919. The next prime is 221151694991. The reversal of 221151694949 is 949496151122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 140846337025 + 80305357924 = 375295^2 + 283382^2 .

It is a cyclic number.

It is not a de Polignac number, because 221151694949 - 2³² = 216856727653 is a prime.

It is a super-2 number, since 2×221151694949² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221151694949.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221151694919) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3334994 + ... + 3400659.

It is an arithmetic number, because the mean of its divisors is an integer number (55289615859).

Almost surely, 2^221151694949 is an apocalyptic number.

It is an amenable number.

221151694949 is a deficient number, since it is larger than the sum of its proper divisors (6768487).

221151694949 is an equidigital number, since it uses as much as digits as its factorization.

221151694949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6768486.

The product of its digits is 1399680, while the sum is 53.

The spelling of 221151694949 in words is "two hundred twenty-one billion, one hundred fifty-one million, six hundred ninety-four thousand, nine hundred forty-nine".