1213451550 has 48 divisors (see below), whose sum is σ = 3343736880. Its totient is φ = 323586720.

The previous prime is 1213451537. The next prime is 1213451563. The reversal of 1213451550 is 551543121.

1213451550 is a `hidden beast` number, since 12 + 134 + 515 + 5 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1213451537) and next prime (1213451563).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 448077 + ... + 450776.

It is an arithmetic number, because the mean of its divisors is an integer number (69661185).

Almost surely, 2^1213451550 is an apocalyptic number.

1213451550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1213451550 is an abundant number, since it is smaller than the sum of its proper divisors (2130285330).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1213451550 is a wasteful number, since it uses less digits than its factorization.

1213451550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 898874 (or 898863 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The square root of 1213451550 is about 34834.6314750135. The cubic root of 1213451550 is about 1066.6144923482.

Adding to 1213451550 its reverse (551543121), we get a palindrome (1764994671).

The spelling of 1213451550 in words is "one billion, two hundred thirteen million, four hundred fifty-one thousand, five hundred fifty".