1225512972 has 72 divisors (see below), whose sum is σ = 3213231840. Its totient is φ = 393361920.

The previous prime is 1225512971. The next prime is 1225512973. The reversal of 1225512972 is 2792155221.

1225512972 is a `hidden beast` number, since 12 + 2 + 551 + 2 + 97 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (1225512971) and next prime (1225512973).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1225512971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 450697 + ... + 453407.

It is an arithmetic number, because the mean of its divisors is an integer number (44628220).

Almost surely, 2^1225512972 is an apocalyptic number.

1225512972 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1225512972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1606615920).

1225512972 is an abundant number, since it is smaller than the sum of its proper divisors (1987718868).

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

1225512972 is a wasteful number, since it uses less digits than its factorization.

1225512972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3183 (or 3178 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 1225512972 is about 35007.3274044164. The cubic root of 1225512972 is about 1070.1368130880.

The spelling of 1225512972 in words is "one billion, two hundred twenty-five million, five hundred twelve thousand, nine hundred seventy-two".