61021907 has 4 divisors (see below), whose sum is σ = 61431600. Its totient is φ = 60612216.

The previous prime is 61021897. The next prime is 61021931. The reversal of 61021907 is 70912016.

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

It is a cyclic number.

It is not a de Polignac number, because 61021907 - 2¹⁸ = 60759763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61021937) 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, 204623 + ... + 204920.

It is an arithmetic number, because the mean of its divisors is an integer number (15357900).

Almost surely, 2^61021907 is an apocalyptic number.

61021907 is a deficient number, since it is larger than the sum of its proper divisors (409693).

61021907 is a wasteful number, since it uses less digits than its factorization.

61021907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409692.

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 61021907 is about 7811.6520019776. The cubic root of 61021907 is about 393.6968366285.

The spelling of 61021907 in words is "sixty-one million, twenty-one thousand, nine hundred seven".