1225154551 has 4 divisors (see below), whose sum is σ = 1227419704. Its totient is φ = 1222889400.

The previous prime is 1225154537. The next prime is 1225154591. The reversal of 1225154551 is 1554515221.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1225154551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1225154591) 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, 1131765 + ... + 1132846.

It is an arithmetic number, because the mean of its divisors is an integer number (306854926).

Almost surely, 2^1225154551 is an apocalyptic number.

1225154551 is a deficient number, since it is larger than the sum of its proper divisors (2265153).

1225154551 is an equidigital number, since it uses as much as digits as its factorization.

1225154551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2265152.

The product of its digits is 10000, while the sum is 31.

The square root of 1225154551 is about 35002.2078017944. The cubic root of 1225154551 is about 1070.0324766688.

Adding to 1225154551 its reverse (1554515221), we get a palindrome (2779669772).

The spelling of 1225154551 in words is "one billion, two hundred twenty-five million, one hundred fifty-four thousand, five hundred fifty-one".