1221400374 has 16 divisors (see below), whose sum is σ = 2494775808. Its totient is φ = 398470952.

The previous prime is 1221400339. The next prime is 1221400409. The reversal of 1221400374 is 4730041221.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1221400339) and next prime (1221400409).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2165322 + ... + 2165885.

It is an arithmetic number, because the mean of its divisors is an integer number (155923488).

Almost surely, 2^1221400374 is an apocalyptic number.

1221400374 is an abundant number, since it is smaller than the sum of its proper divisors (1273375434).

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

1221400374 is a wasteful number, since it uses less digits than its factorization.

1221400374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4331259.

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 1221400374 is about 34948.5389394178. The cubic root of 1221400374 is about 1068.9384102290.

Adding to 1221400374 its reverse (4730041221), we get a palindrome (5951441595).

The spelling of 1221400374 in words is "one billion, two hundred twenty-one million, four hundred thousand, three hundred seventy-four".