1221215020947 has 32 divisors (see below), whose sum is σ = 1811961177600. Its totient is φ = 812904862176.

The previous prime is 1221215020871. The next prime is 1221215020981. The reversal of 1221215020947 is 7490205121221.

It is a happy number.

1221215020947 is a `hidden beast` number, since 1 + 22 + 121 + 502 + 0 + 9 + 4 + 7 = 666.

It is not a de Polignac number, because 1221215020947 - 2⁸ = 1221215020691 is a prime.

It is a super-2 number, since 2×1221215020947² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221215020447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 81499218 + ... + 81514200.

It is an arithmetic number, because the mean of its divisors is an integer number (56623786800).

Almost surely, 2^{1221215020947} is an apocalyptic number.

1221215020947 is a deficient number, since it is larger than the sum of its proper divisors (590746156653).

1221215020947 is a wasteful number, since it uses less digits than its factorization.

1221215020947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19384 (or 19378 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 1221215020947 in words is "one trillion, two hundred twenty-one billion, two hundred fifteen million, twenty thousand, nine hundred forty-seven".